Parental internalizing disorder and the developmental trajectory of infant self-regulation: The moderating role of positive parental behaviors.

Child self-regulation (SR), a key indicator for later optimal developmental outcomes, may be compromised in the presence of parental mental disorders, especially those characterized by affective dysregulation. However, positive parental behaviors have been shown to buffer against such negative effects, especially during infancy when SR shows great plasticity to environmental inputs. The current study investigated the effect of maternal and paternal lifetime and current internalizing disorders on the developmental trajectory of infant SR from 3 to 24 months, and the potential moderating role of positive parental behaviors. A latent growth model revealed that SR increased overall from 3 to 24 months. Mothers' positive parental behaviors demonstrated significant moderation effects, such that maternal lifetime internalizing disorder was associated with higher SR intercept only among those with low levels of positive parental behavior. Mothers' lifetime internalizing disorder was also associated with a lower linear slope in SR development with a moderate effect size. Fathers' current internalizing disorder was significantly associated with a higher intercept and lower linear slope of the SR trajectory. The current study expands the infant SR literature by describing its early developmental trajectory as well as early risk and protective factors within the parent-infant environment, taking into consideration developmental inputs from both parents.