Child Development, xxxx 2018, Volume 00, Number 0, Pages 1–17

Children’s Vulnerability to Interparental Conflict: The Protective Role of Sibling Relationship Quality

Patrick T. Davies, Lucia Q. Parry, and Meredith J. Martin Sonnette M. Bascoe University of Nebraska–Lincoln University of Rochester

E. Mark Cummings University of Notre Dame

This study tested whether the strength of the mediational pathway involving interparental conflict, adolescent emotional insecurity, and their psychological problems depended on the quality of their sibling relationships. = Using a multimethod approach, 236 adolescents (Mage 12.6 years) and their parents participated in three annual measurement occasions. Tests of moderated mediation revealed that indirect paths among inter- parental conflict, insecurity, and psychological problems were significant for teens with low, but not high, quality bonds with siblings. High-quality (i.e., strong) sibling relationships conferred protection by neutraliz- ing interparental conflict as a precursor of increases in adolescent insecurity. Results did not vary as a func- tion of the valence of sibling relationship properties, adolescent sex, or gender and age compositions of the dyad.

Children who witness recurrent destructive inter- attachment, family cohesion), little is known about parental conflict characterized by hostility, negative the potential operation of sibling relationship pro- escalation, and difficulties resolving disagreements cesses as protective factors in the face of discord are at increased risk for experiencing externalizing, between parents (Davies & Cummings, 2006). To internalizing, and attention difficulties (Jouriles, address this significant gap in the literature, the McDonald, & Kouros, 2016). However, it is also the goal of the present investigation was to examine case that most children exposed to high levels of sibling relationship quality as a protective factor acrimony between parents do not experience clini- that interrupts the pathogenic processes underpin- cally significant levels of psychopathology at any ning children’s vulnerability to interparental one time (Cummings & Davies, 2011; Ghazarian & conflict. Buehler, 2010). Therefore, documentation of the Sibling relationships are an important family scope and magnitude of risk associated with inter- context for child development (Feinberg, Solmeyer, parental conflict has increasingly been supplanted & McHale, 2012). Not only do the vast majority of by a second generation of research designed to children grow up with a sibling, but they also identify the sources of resilience for children spend more time interacting with siblings than they exposed to discord between parents (Cummings & do with any other family member (Buist, Dekovic, Davies, 2011; Grych & Fincham, 2001). Despite evi- & Prinzie, 2013). Moreover, higher sibling relation- dence indicating that children’s vulnerability to ship quality is characterized by warmth, closeness, interparental conflict may be buffered by several and problem solving, and low levels of antagonism, family characteristics (e.g., parenting, parent–child conflict, and detachment are predictors of better psychological adjustment in childhood and adoles- cence (e.g., Buist et al., 2013; Dirks, Persram, Rec- This research was supported by the National Institute of Men- chia, & Howe, 2015; McHale, Updegraff, & tal Health (2R01 MH57318). We are grateful to the children, par- ents, and school staff who participated in the project and to the Whiteman, 2012). In highlighting the possibility that project personnel at the University of Rochester and University of Notre Dame. Correspondence concerning this article should be addressed to Patrick T. Davies, Department of Clinical and Social Sciences in © 2018 Society for Research in Child Development Psychology, University of Rochester, Rochester, NY 14627. All rights reserved. 0009-3920/2018/xxxx-xxxx Electronic mail may be sent to [email protected]. DOI: 10.1111/cdev.13078 2 Davies, Parry, Bascoe, Martin, and Cummings siblings may buffer children from the risk posed by we specifically examine whether sibling relation- interparental conflict, other research indicates that ship processes moderate the mediational role of siblings can serve as sources of protection, support, children’s emotional insecurity in the prospective and companionship under stressful conditions. For association between interparental conflict and chil- example, empirical findings indicate that most chil- dren’s psychopathology. As a prevailing expla- dren report seeking contact with a sibling as a natory model, EST proposes that children’s means of coping with interparental quarrels (Jenk- insecurity in the interparental relationship medi- ins, Smith, & Graham, 1989). Likewise, another ates the risk interparental conflict poses for them study identified sibling affection as a protective fac- (Davies & Cummings, 1994). That is, recurring tor in the prospective association between stressful exposure to angry, escalating, and unresolved life events and children’s emotional problems (Gass, conflicts between parents is proposed to increase Jenkins, & Dunn, 2007). children’s psychological problems by directly sen- Despite some preliminary support for the role sitizing their reactivity to threat in the inter- of sibling characteristics as protective factors, parental relationship. research directly examining sibling relationship In the first link in the mediational chain, the quality as a moderator of associations between emotionally arousing and threatening nature of interparental conflict and children’s psychological repeatedly observing interparental conflict is functioning is limited. To our knowledge, only hypothesized to progressively undermine children’s two cross-sectional studies have examined the goal of preserving a sense of safety and security in multiplicative interplay between interparental con- subsequent interparental interactions. Signs of inse- flict and sibling relationships (Grych, Raynor, & curity are manifested in three domains of chil- Fosco, 2004; Jenkins & Smith, 1990). Moreover, dren’s responding to interparental conflict: (a) these investigations yielded inconsistent support intense, prolonged fear and distress reactions; (b) for the moderating role of sibling relationship active attempts to regulate exposure to parental quality. Whereas one study indicated that the link interactions through involvement in and avoidance between interparental discord and child psycho- of the conflicts; and (c) negative internal represen- logical problems was reduced for children who tations of the implications conflict has for them- experienced good sibling relationships (Jenkins & selves and their family. In the second link in the Smith, 1990), another investigation failed to iden- mediational chain, difficulties preserving emotional tify any significant interactions between inter- security are proposed to intensify and proliferate parental conflict and sibling relationship quality to increase children’s vulnerability to poor adjust- in predicting adolescent psychological adjustment ment and psychopathology. Supporting the value (Grych et al., 2004). Although these earlier studies of EST, longitudinal studies have consistently sup- provide a valuable first step in integrating the ported the mediational role of children’s insecurity study of interparental conflict and sibling relation- in prospective associations between interparental ships, the exclusive use of cross-sectional designs conflict and a wide array of psychological symp- may have diluted the sensitivity to identify sib- toms characterized by internalizing, externalizing, ling relationships as moderators of the cascading and attention problems (see Cummings & Miller- sequelae of interparental conflict over time. Fam- Graff, 2015). ily process models share the premise that the In integrating protective models of sibling rela- stressfulness of witnessing interparental conflict tionships with EST, having a supportive relation- gradually increases children’s vulnerability to psy- ship with a sibling may specifically offset the chopathology by progressively altering how they unfolding vulnerability conferred by interparental respond to subsequent difficulties between parents conflict at two developmental points in the medi- (e.g., Davies, Martin, & Sturge-Apple, 2016; Grych ational cascade (Conger & Conger, 2002; Cum- & Fincham, 1990; Repetti, Robles, & Reynolds, mings & Davies, 2011; McHale et al., 2012). In 2011). the first part of the proposed mediational process Accordingly, our study is designed to provide of EST, sibling relationships may impede the pro- a first test of whether mediational pathways cess whereby interparental conflict sensitizes chil- involving interparental conflict, children’s process- dren to experience insecurity in the face of ing and reactivity to parental difficulties, and interparental conflict. For example, siblings have their psychological problems vary as a function of long been regarded as having the capacity to sibling relationship quality. Guided by emotional serve as protective and supportive figures to chil- security theory (EST; Davies & Cummings, 1994), dren in ways that are similar to the roles played Siblings as Buffers of Interparental Conflict 3 by attachment figures (Dunn & Kendrick, 1982; interparental processes and sibling relationship McHale et al., 2012). In support of this thesis, qualities. According to developmental models research has shown that siblings effectively (Cummings & Davies, 2011; Grych et al., 2004), reduced the distress of young children during early adolescence ushers in emerging patterns of stressful separation and reunion episodes in the functioning that may sensitize children to inter- Strange Situation (Stewart, 1983; Stewart & Mar- parental conflict. Relative to younger children, ado- vin, 1984). Likewise, observational findings indi- lescent concerns about security in high conflict cate that sibling positive affect and prosocial homes may be amplified by their increased sensitiv- behavior increase during and following exposure ity to adult problems, longer histories of exposure to anger between adults (Cummings & Smith, to interparental conflict, and stronger dispositions 1993). Taken together, it is possible that siblings to mediate conflict (Cummings & Davies, 2011; may attempt to buffer each other from the stress- Fosco & Grych, 2010; Vu, Jouriles, McDonald, & fulness of witnessing interparental conflict, thereby Rosenfield, 2016). Consistent with this premise, the reducing signs of insecurity in the form of lower prospective relation between interparental conflict levels of emotional reactivity, avoidance, involve- and emotional insecurity was significantly stronger ment, and negative representations in the face of for adolescents than it was for preadolescent subsequent disagreements between parents. children (Cummings, Schermerhorn, Davies, Goeke- At the latter part of the mediational cascade, Morey, & Cummings, 2006). By the same token, high-quality sibling relationships might reduce or sibling relationships are salient socialization con- offset the tendency for children’s prolonged con- texts for children during early adolescence. Within cerns about security in the interparental relation- this developmental period, increases in both posi- ship to proliferate into broader psychological tive (e.g., nurturance, attachment) and negative problems. According to EST (Davies, Martin, & (e.g., antagonism, conflict) characteristics in these Sturge-Apple, 2016), children’s insecurity in the relationships are highly prevalent as adolescents interparental relationship reflects the heightened seek to negotiate a balance between autonomy and saliency of processing and defending against relatedness within the changing parameters of their social threat over approach-oriented goals that sibling relationships (Buhrmester & Furman, 1990; facilitate the intrinsic motivation to acquire social Campione-Barr & Smetana, 2010). Moreover, indi- skills (e.g., cooperation, mutuality, reciprocal altru- vidual differences in the quality of sibling relation- ism in peer relationships), caregiving capacities ships during adolescence are potent predictors of (e.g., empathy, sympathy, prosocial behavior, per- subsequent changes in psychological adjustment spective taking), and mastery of the physical even after controlling for a wide range of family world (e.g., problem solving, autonomous learn- and child covariates (e.g., Solmeyer, McHale, & ing). Difficulties in achieving these goals, in turn, Crouter, 2014; Whiteman, Solmeyer, & McHale, increase children’s risk for psychological difficul- 2015). ties. Conceptualizations of the developmental In summary, the current investigation is functions of sibling relationships support the designed to break new ground by examining sib- notion that healthy sibling processes may counter- ling relationship quality as a protective factor in act this pathogenic cascade. For example, strong each of the links in the mediational pathway sibling bonds may increase the resilience of inse- involving adolescents’ experiences with inter- cure children by serving as role models, mentors, parental conflict, emotional insecurity, and psycho- and guides to effectively negotiating approach- logical problems. As the first prospective analysis oriented challenges in interpersonal (e.g., peer) of the protective role of sibling relationship quality and exploratory (e.g., academic) domains (Jacobs in models of interparental conflict, we employed a & Sillars, 2012; Kramer & Conger, 2009; McHale multimethod (i.e., observational, semistructured et al., 2012). interview, and surveys), longitudinal design with To test these theoretically guided hypotheses, we three annual measurement occasions to authorita- examined whether sibling relationship quality mod- tively test our hypotheses. Following rigorous erated the mediational cascade of interparental con- quantitative guidelines for examining moderated flict, children’s emotional insecurity, and their mediation (Cole & Maxwell, 2003; Maxwell & Cole, psychological problems during early adolescence. 2007), we instituted repeated measures of adoles- We focused on early adolescence because it is a key cent insecurity and psychological problems to per- developmental period for understanding the down- mit a full prospective analysis of whether change at stream implications of the interplay between each part of the mediational chain was moderated 4 Davies, Parry, Bascoe, Martin, and Cummings by sibling relationship quality. To complement the socioeconomic (e.g., parent educational attainment, predominant reliance on questionnaire assessments household income) and structural (e.g., genetic of sibling relationships, we utilized rich, coded nar- relatedness of siblings) characteristics as covariates rative descriptions of the quality of children’s rela- in analyses (e.g., Buist et al., 2013; Davies, Martin, tionships with their closest-aged sibling from a Coe, & Cummings, 2016). semistructured interview with mothers. Consistent with previous research (Buist, 2010; Richmond, Stocker, & Rienks, 2005; Volling & Blandon, 2005), Method our assessment of sibling relationship quality con- Participants sisted of a broad, parsimonious composite indexing both higher levels of positive (i.e., warmth, problem Data for this study were drawn from a longitudi- solving, conflict resolution) attributes and lower nal project on family relationship processes and levels of negative (i.e., destructive conflict, disen- adolescent development. Participants in the larger gagement) characteristics in the dyad. However, study consisted of 280 families with adolescents some research suggests that constructive (e.g., who were recruited through local school districts warmth) and destructive (e.g., conflict) relationship and community centers in a moderately sized characteristics may differ in their developmental metropolitan area in the Northeastern United States implications during adolescence (e.g., Buist et al., and a small city in the Midwestern United States. 2013). Therefore, we conducted follow-up analyses Families were only included in this paper if: (a) to examine whether any significant protective mothers, fathers, and adolescents had regular con- effects of sibling relationship quality in the media- tact with each other (defined as maintaining contact tional cascade are primarily attributable to adoles- for an average of 2–3 days per week during the cents’ exposure to positive relational characteristics, year); and (b) adolescents had at least one sibling their diminished experiences with negative dyadic who was not a twin. These inclusionary criteria processes, or both. resulted in the exclusion of 44 families (i.e., 17 Moreover, given that the nature and sequelae failed to meet the first condition; 27 failed to meet of sibling relationship qualities may vary across the second requirement), yielding a sample of 236 the sex of the adolescent, the sex composition of families. a sibling dyad, the developmental status of sib- Adolescents were in seventh grade at Wave 1 lings (i.e., older vs. younger), and the constella- and, on average, 12.59 years (SD = 0.57; tion of age and sex characteristics of the pairs, range = 11–14). Girls comprised 49% of the sample. we also examine whether any identified protective Median household income of the families was effects of sibling relationship quality are moder- between $55,000 and $74,999 per year. Median edu- ated by these structural characteristics. These cation level of mothers and fathers was between characteristics were selected based on some, albeit some college education and an associate’s degree. inconsistent, empirical and theoretical support for Most parents (i.e., 89%) were married at the outset the possibility that the developmental meaning of the study. For racial background, 74% of adoles- and consequences of the sibling relationship qual- cents identified as White, followed by smaller per- ity may vary by gender, age, and the combina- centages of African American (17%), multiracial tion of gender and age (e.g., Buist, 2010; Buist (8%), and other races (1%). In terms of US ethnicity et al., 2013; Solmeyer et al., 2014). For example, designations, 6% of youth identified as Latino. Ado- Buist (2010) found that sibling relationship quality lescents lived with their biological mother in most was only a significant predictor of greater delin- cases (93%), with the remainder living with an quency for older sister/younger brother pairs. adoptive or stepmother (4%), or a female guardian Likewise, some conceptual models (e.g., social (3%). Children also lived with their biological father learning theory) have proposed that the impact of in most cases (79%), with the remainder of the sam- sibling relationship quality on children’s psycho- ple living with either an adoptive or stepfather logical functioning will be greatest for younger (16%), or a male guardian (5%). The longitudinal and same-sex sibling dyads, given the greater sal- design of the study consisted of three annual mea- ience of vicarious learning (Whiteman, McHale, & surement occasions. Data were collected between Soli, 2011). Finally, to ensure that any significant 2007 and 2011. Retention rates were 93% across moderated-mediation effects were not simply each of the two contiguous waves of data collec- byproducts of the operation of demographic fac- tion, with 85% of the families completing all three tors, we also included several family waves of data collection. Siblings as Buffers of Interparental Conflict 5

For adolescents with more than one sibling, the Cummings, 2004), each parent was asked to inde- sibling closest in age to the adolescent was selected pendently select the three most problematic topics to assess sibling relationship quality. The mean age of disagreement in their relationship that they felt of siblings was 12.63 years (SD = 3.87, range = 2– comfortable discussing. Couples were provided 27 years old). Despite the wide age range of the sib- with a list of common disagreements to use as a lings, 87% of adolescents and their siblings were no guide in the selection process. After this procedure, more than 5 years apart, with the average span partners conferred to select two topics from their being 3.32 years (SD = 2.29). The developmental lists that they both felt comfortable discussing. The status of target adolescents in relation to their sib- couples subsequently discussed each topic for lings was relatively evenly distributed, with target 7 min while they were alone in the laboratory adolescents being: (a) older than siblings in 53% of room. Trained coders rated videotaped records of the dyads, and (b) younger than siblings in 47% of the interparental interactions using five-dimensional the dyads. Sibling dyads were divided fairly evenly scales from the system for coding interactions in with regard to distribution of child sex: 52% were dyads (SCID; Malik & Lindahl, 2004). Raters sepa- same-sex dyads (26% brothers; 26% sisters) and rately coded mothers and fathers for verbal aggres- 48% were opposite-sex pairs (25% target brother–si- sion, defined as the level of hostile or aggressive bling sister; 23% target sister–sibling brother). behaviors and verbalizations displayed by each Finally, within the subsample of opposite-sex pairs individual, and poor problem solving (reverse score of siblings, 56% were older brother/younger sister of the SCID Problem Solving Communication code), dyads, and 44% were older sister/younger brother defined as uncooperative behaviors that hinder pro- pairs. Most dyads were full biological siblings gress in addressing the conflict. At a dyadic level of (88%), followed by smaller percentages of half-sib- analysis, coders also rated negative escalation, lings (6%), step-siblings (2%), adopted (2%), and reflecting the degree to which the couple as a unit other (2%). Most adolescents lived with the target escalates expressions of anger, hostility, and nega- sibling (90%). tivity. Each code is rated on a 5-point scale ranging from 1 (very low)to5(high). Interrater reliability, based on the intraclass correlation coefficients of Procedures and Measures coders’ independent ratings on 19% of the interac- At each of three waves of data collection, fami- tions, ranged from .72 to .90 across five codes = fi lies visited the laboratory twice at one of two data (MICC .83). The ve observational ratings were collection sites. Laboratories at each site were summed together to form a single composite of designed to be comparable to each other in size interparental conflict (a = .85). and quality and included: (a) an observation room that was designed to resemble a living room and Sibling Relationship Quality equipped with audiovisual equipment to capture family interactions, and (b) interview rooms for At Wave 1, a trained experimenter administered completing confidential interview and survey mea- the Sibling Interview for Mothers, a semistructured sures. Teachers also completed survey measures of interview with the mother, designed to assess the adolescent psychological adjustment at the first and quality of sibling relationships in childhood (Bas- third waves. The study was approved by the insti- coe, Davies, & Cummings, 2012). The timing of our tutional review board at each research site. Families Wave 1 sibling measure was guided by quantitative and teachers were compensated monetarily for their calls in the literature to obtain moderator assess- participation. Families were paid between $125 and ments that temporally correspond with or precede $155 per visit depending on the wave. Teachers the proposed predictors (i.e., Wave 1 interparental were paid $25 at each wave. conflict and Wave 2 adolescent emotional insecu- rity; Goodnight, Bates, Newman, Dodge, & Pettit, 2006). We followed conventional procedures for Interparental Conflict assessing sibling relationships in this study by At Wave 1, mothers and fathers participated in focusing the interview on the quality of adolescents’ an interparental interaction task in which they dis- relationships with their closest-aged sibling (e.g., cussed two common, intense interparental disagree- Kim, McHale, Crouter, & Osgood, 2007; Volling & ments that they viewed as problematic in their Blandon, 2005; Whiteman, et al., 2015). The multi- relationship. Following similar procedures in previ- component interview contains questions on the ous research (Du Rocher Schudlich, Papp, & social and emotional characteristics of the target 6 Davies, Parry, Bascoe, Martin, and Cummings sibling dyad. In the first part of the interview, codes to a principal components analysis with vari- mothers rated the level of closeness in the sibling max rotation. Analysis of the eigenvalues (i.e., ≥ 1) dyad on a 5-point scale (1 = not close at all;5= ex- and scree plot of the factors supported a one-factor tremely close). In the middle portion of the inter- solution. Therefore, a single, parsimonious compos- view, mothers responded to more specific questions ite of sibling relationship quality was created by about the nature of sibling interactions (e.g., “What summing the five sibling ratings after reverse-scor- does a typical interaction between them look like?” ing disengagement and conflict so that higher “What sorts of things do they typically talk about scores reflected higher quality sibling relationships when they’re together?”). In the concluding section (a = .78). of the interview, the focus was on understanding the frequency and nature of challenges and dis- Adolescent Insecurity in the Interparental Relationship agreements in the sibling relationship. Mothers first provided ratings of conflict frequency on a 7-point Adolescents completed five subscales of the scale (0 = never;7= several times a day). Ratings Security in Interparental Subsystem (SIS) Scales to were followed by specific questions designed to assess their emotional insecurity at Waves 1 and 2 characterize key parameters of conflicts, including (Davies, Forman, Rasi, & Stevens, 2002). First, the onset (e.g., “How do conflicts typically start?”), SIS Emotional Reactivity subscale consists of nine course (e.g., “Describe what happens next.”“Is items that assess multiple, prolonged experiences of there anything else that typically happens before fear and distress in response to conflict (e.g., “When the conflict ends?”), and endings (e.g., “How do my parents argue, I feel scared.”). Second, the SIS conflicts typically end?”). Additional probes were Avoidance subscale indexes adolescent endorse- used by interviewers to clarify vague or underde- ment of strategies to reduce their exposure to inter- veloped responses. parental conflict (e.g., “I keep really still, almost as Trained coders rated audiotaped records of the if I was frozen.”). Third, the SIS Involvement sub- interview using five-dimensional scales, each rang- scale is designed to assess children’s efforts to ing from 0 (none)to3(high). Three constructive fea- directly regulate and intervene in the conflicts tures of sibling relationship quality consisted of: (a) between their parents (six items; e.g., “I try to solve warmth, defined by the degree of closeness and the problem for them.”). Finally, consistent with intimacy in the sibling dyad (e.g., verbal expres- previous studies (e.g., Davies, Harold, et al., 2002), sions of fondness, physical affection, conversations we utilized the Negative Representations scale con- about intimate issues, sharing of common interests, sisting of the sum of two subscales: the SIS Destruc- prosocial behavior, plans to maintain and tive Family Representations, which assesses strengthen the relationship); (b) conflict resolution, appraisals of the deleterious consequences of inter- characterized by resolving disagreements in ways parental conflict for the family (four items; e.g., that allow siblings to quickly resume friendly inter- “When my parents have an argument, I wonder if actions; and (c) problem solving, as reflected in the they will divorce or separate.”); and the SIS Conflict ability to utilize constructive conflict tactics that are Spillover Representations, defined as children’s likely to be effective in resolving differences (e.g., evaluation that interparental conflict proliferates to efforts to understand the other’s perspective, com- negatively impact their welfare and relations with promising, apologizing, and generating constructive parents (four items; e.g., “When my parents have solutions). Two destructive relationship dimensions an argument, I feel like they are upset at me.”). Pre- included the following: (a) destructive conflict, vious research has supported the validity of this assessing the degree to which the sibling relation- measurement approach (Davies, Forman, et al., ship is characterized by frequent, escalating, and 2002; Davies, Harold, et al., 2002). Internal consis- intense hostility; and (b) disengagement, defined by tencies for Waves 1 and 2, respectively, were .89 high levels of indifference, emotional detachment, and .88 for emotional reactivity, .82 and .85 for and unresponsiveness in the dyad. Interrater relia- avoidance, .73 and .77 for involvement, and .87 and bility, which reflected intraclass correlation coeffi- .87 for insecure representations. cients calculated from coders’ independent ratings of 21% of the interviews, was as follows: Adolescent Psychological Problems warmth = .86; conflict resolution = .88, problem solving = .67; destructive conflict = .92; and disen- To obtain a comprehensive assessment of adoles- gagement = .83. To determine the factor structure cent psychological problems at Waves 1 and 3, of the sibling measures, we submitted the five mothers, teens, and teachers each completed Siblings as Buffers of Interparental Conflict 7 assessments of adolescent problems across three Hyperactivity/Inattention (e.g., “Restless, overac- domains: externalizing, internalizing, and atten- tive, cannot stay still for long,”“Easily distracted, tional difficulties. Mothers completed three scales concentration wanders”), and Emotional Symptoms from the Child Behavior Checklist (CBCL; Achen- (e.g., “Many fears, easily scared,”“Often unhappy, bach, 1991), including: (a) the Externalizing Symp- depressed, or tearful”) subscales from the teacher toms Scale (e.g., “lying or cheating,”“gets in many version of the SDQ (Goodman, 2001). Internal con- fights”); (b) the Internalizing Symptoms Scale, con- sistencies for each of the five-item scales ranged sisting of the Anxious/Depressed and Withdrawn from .68 to .82 (Ma = .75 at Wave 1 and Wave 3). subscales (e.g., “fears certain animals, situations, or Consistent with the child- and parent-report mea- places,”“unhappy, sad, or depressed”); and (c) the sures, we created a single composite of teacher- Attention Problems scale (e.g., “can’t sit still, rest- reported adolescent problems at each wave. The less, or hyperactive,”“can’t concentrate, can’t pay three scales were standardized and averaged attention for long”). Previous studies have provided together at each wave. Scale-level alpha coefficients consistent evidence for the reliability and conver- for each composite were .66 and .65 at Waves 1 gent and discriminant validity of these three CBCL and 3, respectively. scales (e.g., Achenbach, Dumenci, & Rescorla, 2003). Alpha coefficients for the three measures Demographic Covariates across the two waves ranged from .74 to .90 (Ma = .82 at Wave 1 and .83 at Wave 3). To form a Seven covariates were derived from parent parsimonious indicator of maternal reports of ado- reports of demographic characteristics at Wave 1 lescent psychological problems, the three measures including (a) sex of the target adolescent (1 = boy; were standardized and averaged together at each of 2 = girl); (b) sex of the target sibling (1 = boy; the waves. Internal consistency coefficients of the 2 = girl); (c) Wave 1 parental educational level, cal- scales in the composites were .71 at Wave 1 and .75 culated as the average of maternal and paternal at Wave 3. years of education; (d) total annual household To obtain comparable measures of externalizing income based on a 13-point ordinal scale ranging and attentional symptoms, adolescents completed from 1 (< $6,000)to13($125,000 or more); (e) co- the Conduct Problems (five items; e.g., “I fight a residency status of siblings (i.e., living together vs. lot,”“I am often accused of lying or cheating”) and living part); (f) age difference between target ado- Hyperactivity/Inattention (five items; e.g., “Iam lescent and sibling, and (g) genetic relationship restless, I cannot stay still for long,”“I am easily between siblings (i.e., 1 = step, adopted, or other; distracted, I find it difficult to concentrate”) sub- 2 = half sibling; 3 = biological sibling). scales from the Strengths and Difficulties Question- naire (SDQ; Goodman & Scott, 1999). For the assessment of internalizing problems, children com- Results pleted the Center for Epidemiological Studies Descriptive Analyses Depression Scale (CES–D; Radloff, 1977), a 20-item measure indexing emotional problems in the form Table 1 provides the means, standard deviations, of both depressive and anxiety symptoms (e.g., “I and correlations for the variables used in the pri- felt fearful,”“I felt sad”). Reliability and validity mary analyses. As denoted by the bolded coeffi- are well-established for both the SDQ (e.g., Good- cients in the table, correlations among the man, 2001) and the CES–D (e.g., Crockett, Randall, indicators of the higher order constructs of adoles- Shen, Russell, & Driscoll, 2005). Alpha coefficients cent emotional insecurity and psychological prob- for the four scales at each of the waves ranged from lems within each wave were generally moderate to = .64 to .89 (Ma = .74 at Wave 1 and .76 at Wave 3). strong in magnitude (Mr .45). Prior to conducting The three scales were standardized and averaged our primary analyses, we also examined whether together to obtain a single child report measure of rates of missingness in our data set were associated their psychological difficulties at Waves 1 (scale- with any of the 16 primary variables, seven possible level a = .69) and 3 (scale-level a = .69). covariates, and nine additional sociodemographic The final indicator comprised three teacher variables (e.g., parental age, marital status). Two of report measures within three domains of adolescent the 32 analyses were significant, with greater rates psychological problems. Teachers completed the of missingness associated with higher levels of Conduct Problems (“Often fights with other youth interparental conflict (r = .17, p = .01) and negative or bullies them,”“Often lies and cheats”), child representations of interparental conflict 8 Davies, Parry, Bascoe, Martin, and Cummings

(r = .14, p = .03) at Wave 1. Full-information maxi- Multiple measures of adolescent emotional inse- mum likelihood (FIML) methods for estimating curity and multiple informant reports of their psy- data successfully minimize bias in regression and chological problems were specified as indicators of standard error estimates for all types of missing latent constructs. To maximize measurement equiv- data when the amount of missing data is under alence, loadings of each of the indicators of insecu- 20% (Schlomer, Bauman, & Card, 2010). Therefore, rity and psychological problems were constrained given that data in our sample were missing for 6% to be equal across measurement occasions. Correla- of the values, we used FIML to retain the full sam- tions were also specified among all Wave 1 vari- ple for primary analyses (Enders, 2001). We tested ables in the model and between residual errors of the moderating role of sibling relationship quality the same manifest indicators of adolescent emo- in mediational associations involving interparental tional insecurity and psychological problems across conflict and adolescent emotional insecurity and time to account for stability in measurement error psychological problems using a two-stage structural for each indicator. However, for clarity of presenta- equation modeling approach with Amos 25.0 soft- tion, only significant correlations are depicted in the ware (Arbuckle, 2017). figure. In preliminary model estimations, the seven demographic covariates (i.e., sex of target adoles- cent, sex of target sibling, parent education level, Primary Analyses: Sibling Relationship Quality as a family income, co-residency status of siblings, age Moderator of Security Pathways difference between siblings, genetic relationship To test whether the mediational pathways between siblings) were also initially examined as involving interparental conflict and adolescent emo- predictors of the two endogenous (i.e., adolescent tional insecurity and psychological problems varied insecurity at Wave 2 and their psychological prob- as a function of sibling relationship quality, we lems at Wave 3) variables. However, because none specified a total effect moderated-mediation model of the covariates significantly predicted the endoge- that simultaneously specifies sibling relationship nous variables in the model, they were dropped quality as a moderator of associations between: (a) from the analyses to maximize statistical parsi- Wave 1 interparental conflict and Wave 3 adoles- mony. cent psychological problems; (b) Wave 1 inter- The resulting moderated-mediational model, parental conflict and Wave 2 adolescent emotional which is depicted in Figure 1, provided an ade- insecurity; and (c) Wave 2 adolescent emotional quate fit with the data, v2(88, N = 240) = 289.92, insecurity and their psychological problems p < .001, root mean square error of approximation (Edwards & Lambert, 2007). To test the first two (RMSEA) = 0.06, comparative fit index (CFI) = 0.92, components of the model, we examined whether and v2/df ratio = 1.77. Consistent with previous the cross-product of the centered interparental con- research on the mediational role of insecurity, inter- flict and sibling relationship quality variables at parental conflict at Wave 1 predicted greater ado- Wave 1 predicted adolescent insecurity in the inter- lescent insecurity at Wave 2 even after controlling parental relationship at Wave 2 and psychological for adolescent insecurity and psychological prob- problems at Wave 3 after controlling for inter- lems at Wave 1, b = .24, p < .001. Adolescents’ inse- parental conflict, sibling relationship quality, and curity in the interparental relationship at Wave 2, comparable measures of insecurity and psychologi- in turn, predicted their psychological problems at cal difficulties at Wave 1. As the proposed media- Wave 3, b = .26, p < .001, with the inclusion of tor, adolescent insecurity at Wave 2, in turn, was Wave 1 predictors. In contrast, sibling relationship specified as a predictor of their Wave 3 psychologi- quality at Wave 1 was not significantly associated cal problems. In the final part of the moderation with adolescent insecurity at Wave 2, b = À.08, analyses, we specified the cross-products of each of p = .22, or their psychological problems at Wave 3, the four emotional insecurity indicators at Wave 2 b = .02, p = .80. However, of more direct relevance with the Wave 1 sibling relationship composite as to our aims, sibling relationship quality evidenced manifest indicators of a latent variable reflecting the specificity in its role as a moderator. Sibling rela- multiplicative interaction between sibling relation- tionship quality did not moderate associations ship quality and emotional insecurity (see Marsh, between: (a) Wave 1 interparental conflict and ado- Wen, & Hau, 2004). All the predictors were cen- lescent psychological problems at Wave 3, b = .02, tered prior to the creation of the interaction term. p = .75; or (b) Wave 2 adolescent emotional insecu- The latent interaction term, in turn, was examined rity and psychological problems at Wave 3, b = .02, as a predictor of Wave 3 psychological problems. p = .88. However, the interaction between Table 1 Means, Standard Deviations, and Correlations Among the Primary Variables in the Study

MSD 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Wave 1 family predictors 1. Interparental conflict 9.60 3.62 — 2. Sibling relationship quality 8.63 3.00 À.07 — Wave 1 child emotional insecurity 3. Emotional reactivity 14.89 5.79 .10 À.10 — 4. Negative representations 11.01 4.27 .16* À.12 .71* — 5. Avoidance 15.35 5.37 .09 À.09 .63* .50* — 6. Involvement 12.65 3.98 .05 .07 .32* .31* .31* — Wave 2 child emotional insecurity 7. Emotional reactivity 13.97 5.39 .23* À.11 .49* .48* .36* .29* — 8. Negative representations 10.60 4.11 .17* À.07 .29* .38* .14* .07 .70* — 9. Avoidance 14.78 5.32 .14* À.03 .42* .36* .44* .22* .69* .52* — 10. Involvement 12.09 4.12 .13 .04 .34* .28* .22* .57* .46* .33* .48* —

Wave 2 child psychological problems Con Interparental of Buffers as Siblings 11. Mother report 0.01 0.80 À.01 À.28* .13 .11 .02 À.17* .06 .09 .01 À.15* — 12. Teacher report À0.01 0.76 .28* À.15* .16* .27* .05 .01 .03 .04 À.04 À.14 .36* 13. Child report 0.02 0.81 .16* À.13 .33* .37* .27* À.03 .18* .22* .22* .02 .38* .32* — Wave 3 child psychological problems 14. Mother report 0.00 0.80 .12 À.24* .13 .24* .05 À.08 .18* .18* .05 À.08 .71* .32* .36* — 15. Teacher report À0.01 0.76 .10 À.03 .16* .27* .06 .11 .18* .16* .04 À.07 .27* .46* .28* .35* — 16. Child report 0.00 0.75 .10 À.11 .27* .32* .22* .07 .23* .21* .24* .03 .25* .11* .47* .42* .29*

Note. Correlations among indicators of latent constructs are in boldface. *p < .05. fl c 9 ict 10 Davies, Parry, Bascoe, Martin, and Cummings

W1 Interparental .27* Emotion Avoid x Involve Reps x .02 Conflict x Sibling x Sibling Sibling x Sibling Sibling Relationship Quality .16* .99 .70 .49 .70 -.24* * W2 Child Insecurity -.19 .14* W1 Sibling .02 x W1 Sibling Relationship Quality Relationship Quality -.08 .01 W1 Interparental -.07 Conflict .24*

-.32* .22* Wave 1 Child Wave 2 Child Emotional .59* Emotional Insecurity Insecurity .91 * .42 .78 .96 .32 .69 .71 .42 .75 Emotion Avoid Involve Reps -.13 Emotion Avoid Involve Reps .26* -.53* .33* .53* .28*

Wave 3 Child Wave 1 Child * Psychological .75 Psychological Problems Problems .61 .52 .58 .67 .55 .66 Mother Teacher Child Mother Teacher Child

.67* .36* .28*

Figure 1. A total effect moderated-mediation model testing sibling relationship as a moderator of prospective associations among inter- parental conflict and adolescent emotional insecurity and psychological problems. Emotion = emotional reactivity; Avoid = avoidance; Involve = involvement; Reps = negative representations. *p < .05. interparental conflict and sibling relationship qual- indirect path involving interparental conflict, ado- ity at Wave 1 was a significant predictor of adoles- lescent emotional insecurity, and psychological cent insecurity at Wave 2, b = À.24, p < .001. problems was significantly different from 0 at low Consistent with statistical recommendations (e.g., (À1 SD), 95% CI [.04, .16], and medium (0 SD), Aiken, West, & Reno, 1991), the moderating role of 95% CI [.02, .08], but not high (+1 SD), 95% CI sibling relationship quality was first clarified by [À.04, .02] levels of sibling relationship quality. graphically plotting and calculating the simple slopes of interparental conflict at high- (1 SD above Follow-Up Analyses of Generalizability and Specificity the mean) and low- (1 SD below the mean) level of Sibling Moderating Effects values of sibling relationship quality. Low and high values of interparental conflict were, respectively, To further characterize the nature of the interac- demarcated at À1 SD and +1 SD from the mean for tion, we also conducted two more sets of explora- the simple slope plots and analyses. The graphical tory tests. First, we examined whether the strength plot of the interaction is depicted in Figure 2. Sim- of the sibling relationship quality as a moderator of ple slope analyses revealed that Wave 1 inter- interparental conflict varied as a function of several parental conflict significantly predicted Wave 2 structural characteristics of the sibling relationship: adolescent insecurity at low, b = 3.65, p < .001, but (a) developmental status of the target adolescent in not high, b = À0.26, p = .66, levels of sibling rela- the dyad (i.e., older vs. younger age), (b) sex of the tionship quality. In further illustrating moderated adolescent, (c) the gender composition of the dyad mediation, bootstrapping tests indicated that the (i.e., same-sex vs. opposite-sex), and (d) the Siblings as Buffers of Interparental Conflict 11

17

15 Low Sibling Quality High Sibling Quality

13 Wave 2 Adolescent Insecurity

11 Low IPC High IPC

Figure 2. A graphical plot of the interaction between interparental conflict and sibling relationship quality at Wave 1 in predicting sub- sequent change in adolescent insecurity from Waves 1 to 2.

configuration of gender and age with each of the whether the source of moderation in sibling rela- four structural characteristics (i.e., brothers, sisters, tionships is rooted in the presence of greater older sister–younger brother pairs, and older resources, the relative absence of adversity, or both. brother–younger sister dyads) successively con- Thus, we examined whether constructive (i.e., mean trasted with the larger sample of dyads. To increase of warmth, problem solving, and conflict resolu- the parsimony, statistical power, and stability of the tion) and destructive (i.e., mean of measures of analytic solutions, we excluded adolescent psycho- destructive conflict and disengagement) properties logical problems and the latent interaction between of the sibling relationship moderated the link emotional insecurity and sibling relationship quality between interparental conflict and adolescent emo- from the analyses. In the seven resulting models, tional insecurity in separate structural equa- we specifically examined whether the interaction tion modeling. For the two models, we specifically involving interparental conflict, sibling relationship tested whether the interaction involving inter- quality, and each structural characteristic at Wave 1 parental conflict and each sibling relationship predicted greater adolescent insecurity at Wave 2 parameter at Wave 1 predicted greater adolescent after controlling for Wave 1 insecurity, each of the insecurity at Wave 2 after controlling for Wave 1 predictors (i.e., interparental conflict, sibling rela- insecurity and each of the centered predictors (i.e., tionship quality, and the focal structural characteris- interparental conflict, the specific sibling relation- tic), and the two-way interactions among the ship parameter). The moderating role of the sibling predictors. The models fit the data well, v2/df relationship dynamics in the association between ratio ≤ 1.71, CFI ≥ 0.95, RMSEA ≤ 0.05. However, interparental conflict and emotional insecurity was none of the three-way interactions were significant significant for both constructive, b = À.21, p < .001, (all ps ≥ .09): Interparental Conflict 9 Sibling Rela- and destructive, b = .14, p = .02, dyadic characteris- tionship Quality 9 Developmental Status, b = .11; tics. As shown in Figures 3a and 3b, the graphical Interparental Conflict 9 Sibling Relationship Qual- plots demonstrate that the association between ity 9 Sex of Adolescent, b = .08, Interparental interparental conflict and insecurity is not evident Conflict 9 Sibling Relationship Quality 9 Gender for adolescents with high constructive and low Composition of Dyad, b = À.10; Interparental Con- destructive sibling relationships. Simple slope anal- flict 9 Sibling Relationship Quality 9 Brothers, yses further confirmed the protective nature of b = .09; Interparental Conflict 9 Sibling Relation- these sibling properties. Wave 1 interparental con- ship Quality 9 Sisters, b = .02; Interparental flict was a significant predictor of Wave 2 insecurity Conflict 9 Sibling Relationship Quality 9 Older when adolescents experienced low, b = 2.85, Sister–Younger Brother Dyads, b = À.07; and Inter- p < .001, but not high, b = À0.29, p = .63, levels of parental Conflict 9 Sibling Relationship Quality 9 constructive sibling relationship processes. Like- Older Brother–Younger Sister Dyads, b = À.01. wise, interparental conflict was only prospectively Second, because our sibling relationship quality associated with adolescent insecurity under high, measure consists of an amalgamation of construc- b = 2.59, p < .001, but not low, b = 0.26, p = .67, tive and destructive dyadic properties, it is unclear destructive sibling contexts. 12 Davies, Parry, Bascoe, Martin, and Cummings

17

15

13 Low Constructive Sibling Dyads Wave 2 Adolescent Insecurity High Constructive Sibling Dyads 11 Low IPC High IPC a

17

15

13 Low Destructive Sibling Dyads Wave 2 Adolescent Insecurity High Destructive Sibling Dyads 11 Low IPC High IPC b

Figure 3. A graphical plot of the interaction between (a) interparental conflict and constructive sibling relationship properties at Wave 1 in predicting subsequent change in adolescent insecurity from Waves 1 to 2; (b) interparental conflict and destructive sibling relation- ship quality at Wave 1 in predicting subsequent change in adolescent insecurity from Waves 1 to 2.

within a fully lagged prospective design to examine Discussion the protective effects of sibling relationships. In Toward advancing an understanding of sibling rela- supporting predictions, the findings indicated that tionship quality as a source of resilience in children youth emotional insecurity mediated associations exposed to interparental conflict, our paper was between interparental conflict and their psychologi- designed to be the first study to examine sibling cal problems for children with below average or relationship quality as a moderator of the cascading average quality sibling relationships. Conversely, sequelae of interparental conflict over time. Guided the mediational pathway involving interparental by EST (Cummings & Davies, 2011), we tested the conflict, insecurity, and psychological problems was hypothesis that having a strong sibling relationship not significant for teens with strong sibling relation- may disrupt a process whereby interparental con- ships. Analyses of the locus of the moderating effect flict increases children’s risk for psychopathology further revealed that sibling relationship quality by undermining their sense of security in the inter- specifically conferred a protective effect at the first parental relationship. Consistent with calls for a part of the risk cascade of insecurity. Sibling rela- third generation of interparental conflict research tionship quality characterized by warmth, closeness, that integrates the study of moderating conditions and effective management of conflict specifically with mediating mechanisms (Davies & Cummings, moderated the prospective association between 2006), we used a moderated-mediation approach interparental conflict and adolescent emotional Siblings as Buffers of Interparental Conflict 13 insecurity in the interparental relationship. By con- Although these findings require replication trast, in the latter part of the cascade, high-quality within a larger sample that can more powerfully sibling relations failed to alter the magnitude of test the specificity and generalizability of effects adolescent insecurity as an ensuing predictor of across structural and process characteristics of the their subsequent psychological problems. sibling relationship, it does raise questions about In further characterizing the nature of the moder- what other processes may be underlying the protec- ating effect, simple slope and graphical plot analy- tive effects of sibling relationships. Siblings are ses indicated that sibling relationship quality unique by virtue of their capacity to act as both altered the link between interparental conflict and parental figures and peers (Dirks et al., 2015; subsequent change in adolescent insecurity in a McHale et al., 2012). Thus, beyond their possible form that corresponded with a “protective-stabiliz- role as a source of security, sibling relationships ing” effect (Luthar, Cicchetti, & Becker, 2000). Inter- may also have important peer-like functions that parental conflict was unrelated to adolescent buffer children from interparental adversity. For insecurity for teens with strong sibling relation- example, the shared intimacy and warmth in strong ships. The “stabilizing” nature of protective effect sibling relationships may lay the foundation for a was specifically evident in the low levels of insecu- sense of solidarity and may facilitate disclosure and rity exhibited by children with strong sibling rela- validation of perceptions of the self and family that tionships across all levels of exposure to ultimately reduce concerns about security and interparental conflict. Thus, these findings suggest safety (Jacobs & Sillars, 2012; Kramer & Conger, that having a strong sibling relationship may neu- 2009). Likewise, through participation in shared tralize or offset adolescent vulnerability to insecu- activities (e.g., sports, hobbies) and mutual expo- rity in the aftermath of exposure to interparental sure to new extrafamilial (e.g., peer) settings (Jacobs conflict. & Sillars, 2012; McHale et al., 2012), siblings may Why might sibling relationships offset the ten- also divert children’s attention away from the dency for adolescents to become progressively threatening nature of interparental conflicts. Consis- more insecure following exposure to interparental tent with this possibility, some research shows that conflict? Building on a common interpretative the use of distraction predicts subsequent decreases theme in the sibling literature (e.g., Buist et al., in anxiety and depressive symptoms for children 2013; Jacobs & Sillars, 2012; McHale et al., 2012), who experience uncontrollable family and interper- having a strong sibling relationship may provide sonal stressors (see review by Zimmer-Gembeck & teens with protection and emotional support under Skinner, 2016). adverse social conditions. As subsidiary attachment Although the interpretation up to this point has figures (Stewart & Marvin, 1984; Whiteman et al., centered on the protective nature of constructive 2011), siblings may inhibit the intensification of attributes in sibling relationships, our findings also children’s insecurity by shielding teens from inter- highlight how lower levels of destructive character- parental disagreements or helping them to process istics in the dyad may also be a source of resilience and regulate in the aftermath of their exposure to for children. More specifically, our follow-up analy- the conflicts. However, our exploratory analyses ses indicated that lower levels of negative relation- suggest that accessing the sibling relationship as a ship properties conferred the same protective effects source of support and protection may not be the as positive sibling relationship processes. Therefore, primary process underlying the protective role of a these findings suggest that having a civil, but not strong sibling relationship. If security in the sibling necessarily close, bond with siblings may be suffi- relationship is the active mechanism of protection cient to counteract interparental conflict as a risk (Nixon & Cummings, 1999; Whiteman et al., 2011), factor. Several pathogenic processes have been theo- then we might expect that compensatory effects rized to develop in the wake of destructive sibling would be stronger for adolescents who have older relationships including negative family representa- siblings that are more likely to provide, rather than tions, proclivity to experience emotional distress, require, caregiving support. However, our addi- and hopelessness (Buist et al., 2013; Dirks et al., tional analyses did not support this pattern. The 2015). By extension, it is possible that low levels of buffering role of sibling relationship quality, in our sibling conflict and disengagement may confer pro- sample, did not vary as a function of the develop- tection by limiting the development of these emo- mental spacing (i.e., older vs. younger/same age), tional and appraisal diatheses. That is, lower levels gender composition, or age by gender constellation of destructive characteristics in the sibling relation- of the dyad. ship may keep negative expectations about the 14 Davies, Parry, Bascoe, Martin, and Cummings interparental relationship from generalizing into child report measures of sibling dyadic properties. broader concerns about the implications parental Third, although our multidimensional composite of conflict has for the welfare of the broader family sibling relationship quality was based on previous unit and themselves. assessments and recommendations in the literature Questions remain as to why a comparable (e.g., Buist, 2010; Richmond et al., 2005; Volling & protective effect for sibling relationships was not Blandon, 2005), the development of new found for the prospective link between adolescent approaches to capturing relationship properties is insecurity and psychological problems. Guided by an important next step in identifying the protective canalization models (e.g., Davies, Martin, & Sturge- mechanisms conferred by strong sibling bonds. For Apple, 2016; Sroufe, 1997), one possible explanation example, assessing the degree to which sibling rela- is that the increasing stability and potency of inse- tionships fulfill specific functions or provisions (e.g., curity as a precursor of psychopathology becomes safe haven, secure base, instrumental support, so intractable during adolescence that many factors guided learning, observational learning, affiliative are no longer effective as buffers. Consistent with solidarity, distraction from stress) may increase pre- this interpretation, some empirical evidence sug- cision in identifying the specific ways sibling rela- gests that the differential stability of insecurity tionships may buffer children from the stress of increases during the early and middle adolescence observing interparental conflict (Jacobs & Sillars, period (Davies, Martin, Coe, et al., 2016). Moreover, 2012; Kramer & Conger, 2009; Whiteman et al., meta-analytic findings indicated that proxies of 2011). Finally, our analyses of sibling relationship emotional insecurity (e.g., negative emotional reac- quality as a moderator of the mediational role of tivity) more strongly predicted psychological prob- emotional insecurity constitutes a subset of the pos- lems for adolescents than for children within the sible ways sibling bonds may interrupt the patho- age range of 5–19 years (Rhoades, 2008). Alterna- genic cascades resulting from exposure to tively, it is possible that our assessment did not interparental conflict. Thus, examining how sibling sensitively capture the operative sibling relationship relationships might enhance children’s resiliency by properties that buffer highly insecure adolescents diluting the salience of other interparental risk from developing psychological problems. For exam- mechanisms (e.g., children’s social-cognitive apprai- ple, observational and guided learning experiences sals, Grych & Fincham, 1990; neurobiological reac- in strong sibling dyads may be particularly salient tivity to stress; El-Sheikh & Erath, 2011) is an in limiting the risk associated with insecurity by important direction for future research. providing children with a wider repertoire of cop- In conclusion, as the first longitudinal test of the ing strategies, corrective feedback on misunder- moderating role of sibling relationships in models standings about causes (e.g., blaming self for of interparental conflict, our study was designed to parental problems) of interparental conflict, and a break new ground by examining why strong sibling more nuanced perspective on the differences bonds may serve as a source of resilience for ado- between interparental problems and the nature of lescents exposed to elevated interparental conflict. relationships in the broader social world (Kramer & Guided by EST (Davies & Cummings, 1994), we Conger, 2009; Whiteman et al., 2011). specifically examined whether high-quality sibling Limitations of our study also warrant discussion relationships interrupt the pathogenic cascade for a balanced interpretation of our findings. First, whereby interparental conflict poses a risk for ado- because our community sample consisted of pre- lescent psychological problems by increasing their dominantly White families who were, on average, insecurity in the interparental relationship. Results from middle class backgrounds, caution should be of moderated-mediation tests indicated that the exercised in generalizing our findings to other sam- mediational role of emotional insecurity in the link ples. Second, our decision to assess sibling relation- between interparental conflict and adolescent psy- ship quality through coder ratings of maternal chological problems was only significant for teens narratives from a semistructured interview was with poor or average sibling relationships. Analyses guided by our emphasis on limiting the operation further revealed that the compensatory effect of of common method and informant variance with having a strong (i.e., high quality) sibling relation- other key constructs (e.g., adolescent survey reports ship operated by neutralizing the prospective asso- of insecurity) in our model. However, given that ciation between interparental conflict and mothers may not be privy to all important proper- subsequent increases in adolescent insecurity. ties of the sibling relationship, future research Although formulating authoritative translational would benefit from incorporating observational and recommendations from our findings is premature at Siblings as Buffers of Interparental Conflict 15 this early stage of research, a potentially hopeful Conger, R. D., & Conger, K. J. (2002). Resilience in Mid- message for practitioners is that strengthening western families: Selected findings from the first decade sibling relationships may not only directly foster of a prospective, longitudinal study. Journal of Marriage – children’s psychological adjustment but also offer and Family, 64, 361 373. https://doi.org/10.1111/ new approaches to counteracting risks associated j.1741-3737.2002.00361.x Crockett, L. J., Randall, B. A., Shen, Y. L., Russell, S. T., & with experiencing aggressive, unresolved conflicts fi Driscoll, A. K. (2005). Measurement equivalence of the between parents. For example, if our ndings are Center for Epidemiological Studies Depression Scale for replicated, adapting and implementing after school Latino and Anglo adolescents: A national study. 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