Peer victimization appears heritable, but it is unclear whether the traits that confer genetic risk require time and familiarity with a perpetrator to manifest or whether novel and brief interactions can lead to received aggression that demonstrates similar genetic risk. We examined 20-minute, peer-play interactions between 5-year-olds, pairing one twin at a time with an unfamiliar, same-sex peer. "Received aggression" was defined as being the target of aggression (physical or verbal) from the play partner. We found that children receiving aggression were more aggressive during the interaction and gave more commands. Results demonstrated that dominant genetic effects explained 32% of the variance in received aggression. Thus, there appears to be an underlying genetic risk for being aggressed against, even by an unfamiliar peer in a novel situation. We also provided evidence supporting evocative gene-environment correlations between genetic risk (propensity toward aggression) and the likelihood of receiving aggression. These results have implications for the importance that social skills and assertive communication skills training may have in decreasing aggressive interactions between young children.