Previous research suggests that the association between conflictual parent-child relationships and maladjustment among adolescents is influenced by genetic effects emanating from the adolescents. In this study, we examined whether these effects are mediated by childhood aggression. The data come from the Twin study of CHild and Adolescent Development (TCHAD), a Swedish longitudinal study including 1,314 twin pairs followed from age 13-14 to 16-17. Early adolescent aggression, parental criticism, and delinquency in later adolescence were rated by parents and children at different time points. Multivariate genetic structural equation models were used to estimate genetic and environmental influences on these constructs and on their covariation. The results showed that approximately half of the genetic contribution to the association between parental criticism and delinquency was explained by early adolescent aggression. It suggests that aggression in children evokes negative parenting, which in turn influences adolescent antisocial behavior. The mechanism proposed by these findings is consistent with evocative gene-environment correlation.