The bidirectional relationship between peer relationships and bullying: Evidence from cross-lagged analyses among Chinese children.

BACKGROUND: In the digital age, bullying manifests in two distinct forms: traditional bullying and cyberbullying. Children's peer relationships are important predictors of bullying, and bullying in turn predicts peer relationships. However, few researchers have noted the bidirectional relationship between peer relationships and bullying. METHODS: The present study used a two-wave cross-lagged longitudinal design to fill this gap. The potential sex differences were also examined in this relationship. The sample consisted of 527 Chinese children aged 8 to 12 years (M = 9.69, SD = .96; 53.5% female). Participants completed peer nominations for peer acceptance, peer rejection and social dominance, as well as self-reports of traditional bullying and cyberbullying. RESULTS: Results showed that peer rejection at the first time point (T1) significantly and positively predicted traditional bullying perpetration, cyberbullying perpetration and cyberbullying victimization at the second time point (T2). Traditional bullying victimization at T1 significantly and negatively predicted peer acceptance and social dominance at T2. The results also revealed significant male and female differences. For instance, among boys, peer acceptance at T1 significantly and negatively predicted cyberbullying victimization at T2. In contrast, this relationship was not observed among girls. The present findings have important implications for understanding the cyclical relationship between peer relationships and bullying and providing practical guidance for improving peer relationships and reducing bullying.

Theory of Mind and physical bullying in preschool children: the role of peer rejection and gender differences.

BACKGROUND: Preschool represents the budding and initial stage of bullying behavior, where perpetration of physical bullying predominates as the primary form of bullying. An in-depth understanding of the factors linked to preschool physical bullying behavior is crucial for enabling early prevention and intervention strategies. OBJECTIVE: The purpose of this study was to examine the relationship between Theory of Mind and physical bullying behavior in 4-6 years old children in kindergarten and the mediating role of peer rejection and gender in this relationship. METHODS: Data on perpetration of physical bullying and peer rejection were obtained from 310 preschool children (age range = 52-79 months, M = 66.85, SD = 7.04) by the peer nomination method, and their Theory of Mind was measured by the Theory of Mind Development Scale. RESULTS: The results showed that Theory of Mind negatively predicted perpetration of physical bullying in preschool children and that Theory of Mind was related to perpetration of physical bullying in preschool children only through peer rejection. Boys were also found to have a stronger association between peer rejection and perpetration of physical bullying in preschool children than girls. CONCLUSION: Peer rejection may play a mediating role between Theory of Mind and perpetration of physical bullying in preschool children. In addition, the relationship between peer rejection and perpetration of physical bullying appears to be stronger for boys than for girls. This contributes to our understanding of the relationship between Theory of Mind and perpetration of physical bullying in preschool children and has implications for how bullying prevention and intervention can be tailored to the gender of young children.

Potential Mechanism Linking Peer Relationships and Adolescent Prosocial Behavior: Mediation of Cognitive Empathy and Moderations of OXTR and DRD2.

Peers are important socializers of adolescent prosocial behavior. Still, the proximal cognitive and emotional process underlying this link and the sources of individual differences in sensitivity to peer influence have yet to be explored. Utilizing the gene-gene-environment (G × G × E) approach and multi-informant measurement, this study investigated how peer relationships operate to influence adolescent prosocial behavior by examining the mediating role of cognitive and emotional empathy, and the moderating role of the OXTR and DRD2 genes. The study utilized longitudinal data from a community sample of Chinese adolescents (N = 1080, Mage = 13.32 years at T1). Results showed that cognitive empathy rather than emotional empathy mediated the link between peer acceptance/rejection and prosocial behavior. Furthermore, the association among peer acceptance, cognitive empathy, and prosocial behavior was moderated by OXTR and DRD2. Specifically, adolescents with the combinations of AA/AA or G/G genotypes of OXTR/DRD2 benefited more from peer acceptance compared to their counterparts carrying other combined genotypes. The findings highlight cognitive empathy as a proximal process linking peer interaction to prosocial behavior and lend support to the interaction between oxytocinergic and dopaminergic systems on environmental sensitivity.

Profiles of Peer-Rejected Individuals: Their Attitudes toward the Intellectual Disability Population and the Mediating Role of Resilience.

Literature shows that public perceptions toward people with intellectual disability (ID) tend to be negative, perhaps more so than toward any other population with disabilities, causing severe consequences on the quality of life of these people. Understanding factors associated with these attitudes may contribute to better integration of the ID population into society. This study focuses on the predictive role of school-age peer rejection and contemporaneous familial support on attitudes toward people with ID. Specifically, it aims to identify distinct profiles of people who experienced peer rejection during their school years and who experienced various levels of familial support during the rejection period, and to examine the disparities between these profiles regarding attitudes toward people with ID. An additional goal is to examine whether resilience can mediate the association between profiles of peer-rejected individuals and their attitudes toward individuals with ID. The research sample comprised 1063 Israeli adults reporting various levels of peer rejection during school years. Cluster analysis revealed two profiles of peer-rejected individuals that significantly differ in the level of familial support provided in the face of peer rejection. In accordance with the hypotheses, attitudes of peer-rejected individuals with poor familial support were more negative than those with high familial support and the mediating effect of resilience was significant. Findings emphasize the protective role of familial support in the face of peer rejection, contributing to the emerging literature that deals with the long-term effects of peer rejection and poor resiliency resources on negative attitudes toward out-groups.

Is Bullying Always about Status? Status Goals, Forms of Bullying, Popularity and Peer Rejection during Adolescence.

Bullying has been associated with status goals among peers, but this research has not distinguished among forms of bullying, nor included actual status or popularity among peers in an integrated analysis. To this aim, in concurrent correlational data, we examined adolescent status goals as predictors of peer-reported physical, verbal, exclusionary and electronic bullying, and these further as predictors of popularity and peer rejection (N = 256; 67.2% girls; M age = 12.2 years). We also explored potential indirect associations of status goals with popularity and peer rejection via forms of bullying. The findings indicated that verbal bullying was the most common form of bullying. Status goals were positively related to all but physical bullying, yet only verbal bullying partially mediated this association with popularity. Electronic bullying was unrelated to popularity and peer rejection, when controlling for other bullying forms (but was positively related to rejection at the bi-variate level). The findings underscore the importance of assessing bullying as a heterogeneous construct, as related goals and adjustment among peers may depend on its specific form.

The Effectiveness of an Intervention Programme for Reducing Peer Rejection in Early Childhood Education.

In the early years of schooling, peer groups are key to fostering students' overall learning and development. Yet it has been found that around 10% of children suffer from peer rejection in the classroom, with this problem entailing negative consequences both in the short and long term. The problem proves difficult for adults to detect, which usually leads to a delay in measures being taken to intervene and prevent it. This study applies an experimental design with pre-test and post-test measurements in two groups-experimental and control-in order to address the problem of rejection in the early years of schooling. It explores aspects such as sociometric type, degree of victimisation, social and antisocial behaviour, as well as problematic situations among 637 students at six schools. We then implement an intervention programme for socioemotional competence throughout a school year in an effort to improve students' social skills and relationships, focusing specifically on preventing and reducing the rejection experienced by some of these children. The programme comprises 35 teaching activities and strategies that promote the development of competences for student inclusion (curbing aggression, encouraging teamwork, fostering self-esteem, etc.) and that seek to involve all students, teachers, and relatives by offering an array of complementary resources that enrich the initiatives applied (a programme calendar, assessment notebook, questionnaires, related website, material resources). After the intervention programme, it was found that the experimental group had reduced the percentage of students who suffered rejection from 9.9% to 7.3%, although the same was not true of the control group, which went from 9.5% of rejected students to 10.2%. The reduction in the percentage of rejected students in the experimental group after the application of the programme is an encouraging result that invites us to continue working on more comprehensive interventions to prevent and reduce this phenomenon.

Is teacher preference associated with aggressive behavior among Chinese adolescents: The mediating role of peer rejection and rejection sensitivity.

Few studies have explored the potential impact of teacher preferences on students' peer relationships and their broader psycho-behavioral growth from the perspective of classroom peer ecology. To remedy this research gap, this study hypothesized and tested a serial mediation model in which teacher preference is related to adolescents' aggressive behavior via the indirect paths of forming peer rejection and shaping rejection sensitivity. Using a longitudinal design, two-wave data were obtained from 2270 Chinese adolescents (initial age = 13.93 ± 0.59, 50.7% boys) over 6 months. The results revealed that teacher preference was negatively associated with aggressive behavior in adolescents, and the mediation model indicated peer rejection and rejection sensitivity served as serial mediators between this link. Additionally, the current study examined the unique affiliations of anxiety and anger about rejection with aggressive behavior respectively, with results supporting them as distinct constructs and highlighting the significance of research integrating both forms of rejection sensitivity. Differences were also identified regarding the role of anxious rejection sensitivity in predicting proactive and reactive aggressive behaviors. The educational implications of these findings and directions for forthcoming research were discussed.

The association between peer rejection and behavior problems of migrant adolescents in China: A moderated mediation model of delinquent peer affiliation and parenting.

Facing a stressful environment of peer rejection and discrimination, Chinese migrant adolescents are at high risk of developing behavior problems while receiving insufficient family support. In this context, the current study aimed to explore the pathway from peer rejection to adolescent behavior problems via the mediating role of delinquent peer affiliation and with the moderating roles of parental company and parental monitoring taken into consideration. A sample of 2041 migrant adolescents (46.2% female, mean age = 13.595) was drawn from the first and second waves of the China Education Panel Survey (CEPS) for running a moderated mediation model. The results demonstrated that peer rejection positively predicted behavior problems through the mediator of delinquent peer affiliation (indirect effect = 0.007, 95% CI = [0.003, 0.014]). This mediating mechanism was moderated by parental company and by parental monitoring. Our study deepened the theoretical understanding and application of the general strain theory by showing how the interaction of peer stressors and parenting elements affected the behavior of migrant adolescents in a Chinese context. Further studies could pay more attention to the dynamic interplay between the family and peer systems, especially for rejected and marginalized adolescent groups. Limitations and implications for future school-based and family-based practices are also discussed.

A Developmental Cascade Analysis of Peer Rejection, Depression, Anxiety, and Externalizing Problems from Childhood through Young Adulthood.

The need to belong with peers is an essential component of development, and when individuals face peer rejection they often experience a host of negative outcomes, including internalizing and externalizing problems. There exists conflicting evidence whether peer rejection precedes, succeeds, or reciprocally influences psychopathology. This study used two longitudinal community samples recruited from Portuguese schools with data from middle childhood through early adulthood. The obtained data measured mean levels and assessed stability of peer rejection, and peer rejection's association with demographic and psychopathology variables concurrently across development. Analyses fit developmental cascade models of peer rejection, depression, anxiety, and externalizing problems. Mean peer rejection levels remained relatively stable over time, and peer rejection scores were mildly to moderately correlated at measurement points closer together but attenuated at timepoints that were further apart in time. At some timepoints, age, and parental SES and education were associated with peer rejection. Peer rejection was associated with depression, anxiety, and externalizing problems concurrently at each time point (r = ~0.3-0.5). Developmental cascade models supported depression and anxiety temporally preceding peer rejection and some reciprocal relationships between depression and peer rejection. Anxiety was a robust temporal precedent of psychopathology and peer rejection.

Trajectories of physical and relational aggression across early childhood: Relations with peer risk factors.

The goal of the current study was to examine trajectories of relational and physical aggression in early childhood and evaluate peer predictors of these trajectories (i.e., peer rejection, relational victimization, and physical victimization). The study spanned three-time points (T1 in the spring, T2 in the fall, and T3 in the spring) in early childhood (N = 300; 44.0% girls; Mage = 44.70 months, SD = 4.38; 3.0% African American/Black, 7.6% Asian/Asian American/Pacific Islander, 1.0% Hispanic/Latinx, 11.3% multiracial, 62.1% White, and 15.0% missing/unknown). Observations of peer victimization and teacher report of peer rejection were collected at T1, and teacher report of aggression was collected at all time points. Results from piecewise latent growth models demonstrated that both forms of aggression decreased from T1 to T2 as children entered a new classroom and increased from T2 to T3 as they remained in that classroom. The increase in physical aggression from T2 to T3 was only significant for boys. Peer rejection at T1 emerged as a predictor of both intercepts and slopes from T1 to T2, and physical victimization predicted the physical aggression intercept and physical aggression slope from T1 to T2. Children high on these peer risk variables had higher initial levels of aggression, followed by a greater decrease in aggression from T1 to T2. Results underscore the importance of studying incremental change in aggression in early childhood and suggest that children who experience negative peer treatment have greater fluctuations in aggression over time.

Bullying perpetration and social status in the peer group: A meta-analysis.

INTRODUCTION: Associations between bullying perpetration and social status vary, not only between different facets of social status but also between bullying in primary versus secondary school. The main aim of the present study was to meta-analyse existing evidence regarding the prospective associations between bullying perpetration and various facets of social status, that is, popularity, peer acceptance, peer rejection, and social preference. METHODS: Electronic databases were searched to identify studies on bullying perpetration and later social status published up to January 17, 2022. Multilevel random effects models were performed using Metafor and differences in effect sizes as a function of substantive and methodological moderators were tested. RESULTS: In total, 116 effects were included from 18 publications, reporting on 17 different samples and more than 15,000 participants (mean age bullying assessment = 11.57 years, on average 51% female participants). Most samples were from the United States (7) or Europe (7). Overall, bullies were more popular, but also more rejected and scored lower on social preference compared with non-bullies. These associations remained when effects were adjusted for previous social status and other confounders. No link between bullying perpetration and acceptance was found. There was little evidence that effect sizes differed as a function of moderators. CONCLUSIONS: Bullies become more popular over time, but also have a higher risk of being rejected and being less socially preferred. Bullying perpetrators are more popular but also more rejected by their peers. There is no evidence that these links differ depending on sex or age at which perpetrators bully, reporter or type of bullying.

Adolescent girls' cardiovascular responses to peer rejection: exploring the impact of early life stress.

Detrimental effects of early life stress on cardiovascular health are evident in adolescence. Cardiovascular reactivity and recovery in response to interpersonal stress may be a mechanism. This study aimed to evaluate if adolescent girls with higher early life stress demonstrated greater cardiovascular reactivity and slower recovery to peer rejection. A sample of 92 adolescent girls (age: M = 13.24) self-reported early life stressors. Systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) were continuously measured before, during, and after a laboratory peer rejection paradigm. Counter to hypotheses, adolescent girls with higher early life stress had lower, not higher, HR during the recovery period. Early life stress was not associated with SBP or DBP recovery. Additionally, early life stress was not associated with SBP, DBP, or HR reactivity. Future research is needed to assess if blunted cardiovascular reactivity to interpersonal rejection during adolescence is a mechanism linking early life stress and later cardiovascular disease risk in women.

The association between peer rejection and aggression types: A meta-analysis.

BACKGROUND: Although previous studies have assessed the association between peer rejection and aggression, the results are mixed. OBJECTIVE: This article presents a meta-analysis of the association between peer rejection and aggression types (overt vs. relational) among children and adolescents. PARTICIPANTS AND SETTING: A total of 61 eligible studies with 70 independent effect sizes were included in the analysis (45,966 participants, Mage = 10.34, SD = 3.13). METHODS: First, random-effects meta-analyses were conducted to explore the association between peer rejection and aggression types (overt vs. relational). Next, moderation analyses were conducted based on the Q statistics for categorical variables (culture, reporting method of peer rejection, reporting method of aggression) and the meta-regression analyses for continuous variable (age). RESULTS: Peer rejection was positively correlated with overall aggression (r = 0.42, 95 % CI [0.38, 0.47], p < 0.001), overt aggression (r = 0.46, 95 % CI [0.38, 0.54], p < 0.001) and relational aggression (r = 0.43, 95 % CI [0.35, 0.51], p < 0.001). This correlation was positive for each type when controlling for other form of aggression. Moderation analyses suggested that reporting method of aggression (self-report vs. peer-nomination vs. adult-report vs. observation), reporting method of peer rejection (self-report vs. peer-nomination vs. adult-report) and culture (collectivist vs. individualist) were moderators of the association between peer rejection and overall aggression. Culture moderated the association between peer rejection and overt aggression, while age moderated the association between peer rejection and relational aggression. CONCLUSIONS: The findings showed a strong positive association between peer rejection and aggression, although this association varied by aggression type and other moderating variables.

Bidirectional Associations of Prosocial Behavior with Peer Acceptance and Rejection in Adolescence.

As most studies on the link between peer status and prosocial behavior are cross-sectional, conducted with children, and operationalize status as the difference between acceptance and rejection, it remains unclear whether peer acceptance and rejection are consequences or prerequisites of prosocial behavior in adolescence. To fill this gap, this study examines the bidirectional associations of prosocial behavior with peer acceptance and peer rejection with data collected at 3 time points, 6 months apart, in a sample of 660 early Chilean adolescents (M = 12.94, SD = 0.62; 55.1% boys). Cross-lagged panel analyses showed that prosocial behavior positively predicted future peer acceptance, whereas peer acceptance had no significant effect on future prosocial behavior. The association between rejection and prosocial behavior was negative and bidirectional between Time 1 and Time 2. When a new academic year began, between Time 2 and Time 3, prosocial behavior negatively predicted rejection, whereas rejection in the previous grade level was positively associated with prosocial behavior at the beginning of the next grade. Multi-group panel analyses did not detect significant differences between boys and girls in the cross-lagged associations of prosociality with peer acceptance and peer rejection. The results suggest that acting prosocially can make adolescents better liked by their peers and highlight the possible importance of the transition to a new academic year for the prosocial behavior of previously rejected students. Implications for future research on peer relations are discussed.

The brain in social context: A systematic review of substance use and social processing from adolescence to young adulthood.

Substance use escalates between adolescence and young adulthood, and most experimentation occurs among peers. To understand underlying mechanisms, research has focused on neural response during relevant psychological processes. Functional magnetic resonance imaging (fMRI) research provides a wealth of information about brain activity when processing monetary rewards; however, most studies have used tasks devoid of social stimuli. Given that adolescent neurodevelopment is sculpted by the push-and-pull of peers and emotions, identifying neural substrates is important for intervention. We systematically reviewed 28 fMRI studies examining substance use and neural responses to stimuli including social reward, emotional faces, social influence, and social stressors. We found substance use was positively associated with social-reward activity (e.g., in the ventral striatum), and negatively with social-stress activity (e.g., in the amygdala). For emotion, findings were mixed with more use linked to heightened response (e.g., in amygdala), but also with decreased response (e.g., in insula). For social influence, evidence supported both positive (e.g., cannabis and nucleus accumbens during conformity) and negative (e.g., polydrug and ventromedial PFC during peers' choices) relations between activity and use. Based on the literature, we offer recommendations for future research on the neural processing of social information to better identify risks for substance use.

Connecting the dots: social networks in the classroom and white matter connections in the brain.

BACKGROUND: Peer connections in school classrooms play an important role in social-emotional development and mental health. However, research on the association between children's peer relationships and white matter connections in the brain is scarce. We studied associations between peer relationships in the classroom and white matter structural connectivity in a pediatric population-based sample. METHODS: Bullying and victimization, as well as rejection and acceptance, were assessed in classrooms in 634 children at age 7. White matter microstructure (fractional anisotropy (FA), mean diffusivity (MD)) was measured with diffusion tensor imaging at age 10. We examined global metrics of white matter microstructure and used Tract-Based Spatial Statistics (TBSS) for voxel-wise associations. RESULTS: Peer victimization was associated with higher global FA and lower global MD and peer rejection was associated with lower global MD; however, these associations did not remain after multiple testing correction. Voxel-wise TBSS results for peer victimization and rejection were in line with global metrics both in terms of direction and spatial extent of the associations, with associated voxels (pFWE <.05) observed throughout the brain (including corpus callosum, corona radiata, sagittal stratum and superior longitudinal fasciculi). CONCLUSIONS: Although based only on cross-sectional data, the findings could indicate accelerated white matter microstructure maturation in certain brain areas of children who are victimized or rejected more often. However, repeated measurements are essential to unravel this complex interplay of peer connections, maturation and brain development over time.

Peer Status as a Potential Risk or Protective Factor: A Latent Profile Analysis on Peer Status and Its Association with Internalizing Symptoms in Adolescents with and without Parental Physical Abuse Experience.

Research has well established that parental physical abuse experiences can lead to devastating consequences for adolescents, with peer relationships acting as both protective and risk factors. With the person-centered latent profile analysis (LPA), we analyzed questionnaire data from a cross-sectional study in 2020 composed of a sample of 1959 seventh-grade high school students from Switzerland. This study investigated and compared peer-status profiles combining peer acceptance and peer popularity for adolescents with and without parental physical abuse experiences. We conducted a multinomial logistic regression analysis to investigate further depression, anxiety, and dissociation as predictors of profile membership. With LPA, we identified three distinct profiles for adolescents within the subgroup with experiences of parental physical abuse (n = 344), namely liked, liked-popular, and rejected-unpopular. Within the subgroup of adolescents without parental physical abuse experiences (n = 1565), LPA revealed four profiles, namely liked, liked-popular, rejected-unpopular, and average. For adolescents with parental physical abuse experiences, higher levels of dissociation significantly indicated they were more likely to belong to the rejected-unpopular group than belong to the liked group. Anxious students without experiences of parental physical abuse were more likely to belong to the rejected-unpopular and liked profiles than belong to the liked-popular and average profiles. These findings clearly argue for a deeper understanding of the role of parental physical abuse when analyzing the relationship between dissociation and anxiety and peer status. Operationalizing peer status with the four individual dimensions of likeability, rejection, popularity, and unpopularity was valuable in that the role of peer rejection with respect to different internalizing symptoms became apparent.

The Perception of School Life From the Perspective of Popular and Rejected Students.

The experience of peer rejection in the classroom, an environment in which students spend a large part of their time, is accompanied by a sense of social pain which can have a profound effect on self-perception and attitude toward the overall school environment. These attitudes can be subsequently reflected in the student's behavior at school and in his/her school success. The research aims to identify differences in the perception of school life (interpersonal and intrapersonal) among rejected and popular upper-primary school students. For this purpose, the sociometric nomination method and a questionnaire measuring the student's perception of the school environment were used. From a total of 1,625 students (aged 11-15) from 20 schools, 312 students with the status of popular (liked) and rejected (disliked) were included in the research. The multivariate analysis of covariance (with age and gender as covariates) results revealed no significant differences between the two contrasting groups (popular and rejected) in terms of the perception of school life (interpersonal and intrapersonal). The results of the research indicated a different perception of the school environment within the groups of rejected and popular students rather than differences between the groups. Both the rejected and popular students report contradictory attitudes toward school life. Half of the students indicated that they feel lonely at school and have no confidence in teachers, considering the school a place where they do not like to learn, where they are troubled and where they do not like to talk to their classmates. Perhaps counterintuitively, a larger number of popular students stated that they feel lonely than did the rejected students from the class. Although the results do not paint a very positive picture of perceptions of the school environment, this should be seen as an opportunity to develop active class work with a greater emphasis on strengthening collective trust in the school.

School Bullying-The Silent Epidemic: A Cross-Sectional Study of Factors Associated With Peer Victimization Among Lebanese Adolescents.

The objective of this study was to evaluate bullying at school and identify the factors associated with it among a sample of Lebanese school adolescents. A cross-sectional study was carried out between April 2014 and June 2014, using a convenient sampling of Lebanese students in private schools from Beirut and Mount Lebanon. The results showed that 712 (18.1%) adolescents had been bullied in the past 2 months (95% CI [0.169, 0.192]). A backward logistic regression, taking "being bullied in the last 2 months" as a dependent variable, showed significantly lower odds of being bullied in the last 2 months in those who find it easy (adjusted odds ratios [aOR] = 0.434) and very easy (aOR = 0.391) to talk to their father, and having some close male or female friends compared with none. Furthermore, significantly higher odds of being bullied were found among males compared with females (aOR = 0.664), having a best friend who smokes sometimes compared with never (aOR = 1.389), and a father who drinks everyday compared with never (aOR = 1.621). This study was able to shed light on a problem that sometimes goes silent in schools and has a negative impact on the mental health of teenagers. Indeed, the results of our study showed that peer victimization was closely linked to clinically relevant mental health issues. In addition, factors such as parental and peer support could protect against the negative effects of bullying.

Genotype-environment correlation by intervention effects underlying middle childhood peer rejection and associations with adolescent marijuana use.

Aggressive behavior in middle childhood can contribute to peer rejection, subsequently increasing risk for substance use in adolescence. However, the quality of peer relationships a child experiences can be associated with his or her genetic predisposition, a genotype-environment correlation (rGE). In addition, recent evidence indicates that psychosocial preventive interventions can buffer genetic predispositions for negative behavior. The current study examined associations between polygenic risk for aggression, aggressive behavior, and peer rejection from 8.5 to 10.5 years, and the subsequent influence of peer rejection on marijuana use in adolescence (n = 515; 256 control, 259 intervention). Associations were examined separately in control and intervention groups for children of families who participated in a randomized controlled trial of the family-based preventive intervention, the Family Check-Up . Using time-varying effect modeling (TVEM), polygenic risk for aggression was associated with peer rejection from approximately age 8.50 to 9.50 in the control group but no associations were present in the intervention group. Subsequent analyses showed peer rejection mediated the association between polygenic risk for aggression and adolescent marijuana use in the control group. The role of rGEs in middle childhood peer processes and implications for preventive intervention programs for adolescent substance use are discussed.