Family systems research has identified two key processes (spillover and compensatory), linking interparental relationship quality to the parent-child relationship. However, previous research has focused on the parent as the sole initiator and had not often considered the role of the child in these processes. The present study adds to the literature by leveraging a genetically informed design to examine possible child evocative effects on spillover and compensatory processes. Participants were from a longitudinal parent-offspring adoption sample of 361 linked sets of adoptive parents of an adopted child (57% male), and the child's birth parents. Adoptive parents reported on child pleasure and anger at 18 months and the interparental relationship at 27 months. Parent-child interactions were observed at child age 6 years, and heritable influences were assessed via birth mother self-report at 5 months. Our results indicated a dampening effect where higher interparental warmth at child age 27 months was associated with less adoptive mother-child coercion at child age 6 years, and a compensatory effect where higher interparental conflict was associated with more adoptive father-child positive engagement. Moreover, our results indicated child-driven effects via both genetic and environmental pathways. Specifically, higher levels of birth mother negative affect (heritable characteristic) were associated with lower levels of adoptive father-child coercion. Also, child anger was positively associated with interparental conflict, and child pleasure was positively associated with interparental warmth. These findings support findings from the family literature with evidence of compensatory mechanisms, while also highlighting the active role children play in shaping family interactions.