Early family adversity predicts peer outcomes in middle childhood: A genetically-informed twin study

Children acquire new social skills and validate their own self-concept within peer relationships (Boivin, Vitaro, & Poulin, 2005). Although few genetically informative studies have examined peer relationships, we hypothesize... [ view full abstract ]

Children acquire new social skills and validate their own self-concept within peer relationships (Boivin, Vitaro, & Poulin, 2005). Although few genetically informative studies have examined peer relationships, we hypothesize both genes and the shared environment contribute to peer outcomes. Furthermore, early adversity is known to influence later behavior, therefore we hypothesize that early family stress during toddlerhood would increase victimization and decrease peer acceptance and prosocial behaviors in middle childhood. The sample included 194 twin pairs from the Arizona Twin Project (Lemery-Chalfant et al, 2013). Early Adversity is the first principal component of Parenting Daily Hassles, low perceived MOS social support, punitive punishment (Parental Responses to Child Misbehavior), home chaos (Confusion, Hubbub, and Order Scale), CES-D maternal depression, and low maternal emotional availability. Early adversity was assessed when the twins were 30-months and parents reported on Health and Behavior Questionnaire peer relationships when the twins were 8 years old. Mixed model regression analyses indicated that early adversity predicted more peer victimization, t(93.64) = 4.045, p < .001, less peer acceptance, t(94.275) = -3.154, p = .002, and fewer prosocial behaviors, t(99.211) = -3.797, p < .001. The CE model fit best for victimization (shared 68% and nonshared 32% environment), and peer acceptance (51% shared, and 49% nonshared environment). In contrast, prosocial behaviors had a large genetic component (49%), as well as shared environment (38%). Peers play an important role in shaping child development, especially because children in most cultures spend the majority of their day around age mates at school. Our results highlight the importance of early childhood environments and elucidate the contributions of the shared and nonshared environment to peer relationships in middle childhood. Future analyses include testing whether early adversity moderates ACE influences on peer outcomes. R01HD079520 R01HD086085