Guided by multiple theories illustrating the transactional nature of the relation between parents' and children's behaviors, the present meta-analysis provides synthesized evidence on the strength of child-driven effects in eliciting changes in parents' psychological stress and parenting practices. A meta-analysis of 45 independent samples with 640 effect sizes found significant positive associations between children's externalizing behaviors and parents' subsequent functioning (r = .087, 95% CI [.07, .10]). These associations were net of parents' functioning at baseline, and the strength of these associations was statistically comparable with the effects of parents on children's externalizing behaviors (r = .075, 95% CI [.06, .09]). In addition, the strength of the child-driven effects did not vary as a function of child gender, age, or the time interval between assessments. The implications of these findings with respect to research on the dynamic relation between parenting functioning and children's adjustment are discussed. (PsycInfo Database Record (c) 2021 APA, all rights reserved).