Abstract Child anger and parental negativity are associated, but directionality and underlying mechanisms during early childhood remain unclear. This study examined bidirectional associations using a longitudinal twin design with 310 same-sex twin pairs (51% female; 89.6% White) assessed yearly ages 3–5 years and primary caregivers. Biometric autoregressive latent trajectory models separated within-person from between-person effects. At the within-person level, results indicated child-driven effects where increases in child anger predicted increases in parental negativity, whereas parent-driven effects were not significant. Child-driven effects were primarily genetic, suggesting evocative gene-environment correlation. At the between-person level, trait-like differences in child anger correlated with trait-like differences in parental negativity, primarily due to genetic factors. Findings indicate children's genetically influenced anger characteristics as drivers of parent–child dynamics.
Liu et al. (2026) studied this question.