Research has extensively examined how a poor family climate influences internalizing problems in children. However, studies investigating the directional relationship between children’s internalizing issues and family difficulties, particularly in Chinese populations, remain limited. To address this gap, the current study employed a longitudinal design involving three rounds of surveys with 282 elementary school students (45.74% girls, Mage = 9.73 ± 1.54 years at Time 1) and their parents. Cross-lagged panel model analyses revealed several key findings: children’s internalizing problems consistently predicted subsequent family difficulties, while family difficulties did not significantly affect children’s internalizing problems. Additionally, parenting flexibility at Time 2 (T2) mediated the relationship between children’s internalizing problems at Time 1 (T1) and family difficulties at Time 3 (T3). Children’s executive functioning at T2 also mediated the association between internalizing problems at T1 and family difficulties at T3. These findings underscore the importance of enhancing children’s executive functioning and improving parenting flexibility to mitigate the negative effects of children’s internalizing problems on family dynamics.