Harsh discipline mediates the association between parenting stress and internalizing problems in children and adolescents: survey-based and online intervention evidence

Background Parenting stress evokes harsh discipline and induces internalizing problems in children and adolescents. To test this hypothesis, this study examined the potential mediating role of harsh discipline in the association between parenting stress and internalizing problems in children and adolescents while considering the moderating effect of emotion regulation. Methods Two studies were conducted: Study 1 was a cross-sectional survey using questionnaires ( N = 971), and Study 2 implemented a three-week online parental intervention training program combining courses and psychological diary recording ( N = 123). Results Both studies consistently demonstrated that harsh discipline mediated the link between parenting stress and internalizing problems in children and adolescents. Furthermore, acceptance and cognitive reappraisal reduced the effect of parenting stress on harsh discipline, whereas distraction and rumination enhanced it. Expressive suppression had no significant moderating effect. The intervention enhanced parents’ emotion regulation (increased acceptance), reduced parenting stress and alleviated internalizing problems in children and adolescents, with preliminary evidence of reduced harsh discipline. Conclusion These findings clarify the psychological mechanisms through which parenting stress influences child adaptiveness and underscore the value of interventions focused on emotion regulation in mitigating parenting stress, harsh discipline and enhancing child mental health.