Background <p>Research indicates the intergenerational effects of parents’ adverse childhood experiences on anxiety and depressive symptoms in offspring. However, few studies have investigated the longitudinal mechanisms linking parents’ adverse childhood experiences and offspring anxiety and depressive symptoms. This study aimed to explore the longitudinal link between parents’ adverse childhood experiences and offspring anxiety and depressive symptoms through a series of mediating effects of parents’ psychological distress and children’s sleep problems in Chinese parent–child dyads.</p> Methods <p>36% of the participants were lost to follow up. A total of 539 parent–child dyads participated in three survey waves, each one year apart. Parents completed measures on adverse childhood experiences and psychological distress at T1 (2022), children’s sleep problems at T2 (2023), and children’s anxiety and depressive symptoms at T3 (2024). Chain mediation analysis was conducted using Hayes' PROCESS macro (Model 6).</p> Results <p>We found that the total effect of this model was 0.21 (95% CI [0.07, 0.35]). Moreover, parental psychological distress and children’ sleep problems mediated the associations between parents’ adverse childhood experiences and children’s anxiety and depressive symptoms, separately (b = 0.13, 95% CI = [95% CI [0.04, 0.20]; b = 0.03, 95% CI = [0.01, 0.06]) and sequentially (chain mediation effect = 0.01 (95% CI [0.01, 0.03]).</p> Conclusions <p>This study underscores the significance of parents’ psychological distress and children’s sleep problems in the pathway between parents’ adverse childhood experiences and offspring anxiety and depressive symptoms. Consequently, findings highlight potential targets for preventive interventions to parents exposed to adverse childhood experiences to prevent anxiety and depressive symptoms and sleep problems in children.</p>