The quality of young children\u27s peer relationships is important for their development, and it is assumed that parenting and self-regulation skills shape children\u27s behavior when interacting with peers. In this multi-informant-multi-method study, we examined the direct and mediated associations between preschool parenting, children\u27s behavioral self-regulation, and peer aggression and peer relationship problems in elementary school-aged children and extended previous work by examining both positive and negative parenting of both mothers and fathers. In a large community sample (n = 698) of parents and children who were between 1 and 6 years old, we obtained information on observed maternal sensitivity, mother- and father-reported harsh discipline, observed child self-regulation, and child-reported aggression towards peers, peer rejection and victimization. Results from a structural equation model showed that maternal sensitivity was prospectively associated with children\u27s behavioral self-regulation and that lower levels of behavioral self-regulation were associated with higher levels of children\u27s peer aggression and peer relationship problems. However, children\u27s behavioral self-regulation did not mediate the association between maternal sensitivity and peer relationship problems. In addition, higher levels of paternal, but not maternal, harsh discipline were directly associated with more peer relationship problems, but again no mediation was found. The results highlight the importance of maternal sensitivity for children\u27s behavioral self-regulation and the role of paternal harsh discipline for the quality of children\u27s later peer relationships. Our findings suggest it is important to take maternal and paternal parenting practices into account as they might have different effects on the child
