The main goal of this study is to analyze the generalization effect of interparental conflict in sibling relationships and child adaptation. A Spanish sample made up of 100 children, aged between 7 and 18 years, was used. Interparental conflict was the independent variable, and child maladaptation the dependent variable, whereas sibling relationship and parenting style were the mediating variables. Extraversion was controlled as a covariate. Variables were measured through self-report questionnaires. The mediation model was supported. Results showed that more restrictive parental styles and a decrease of positive sibling exchanges were both associated with child maladaptation, which revealed this generalization process. The relation of these results with previous literature and future implications are discussed.