Unpredictability in caregiver-child relationships: Impact on child verbal abilities and externalizing problems

This study examined longitudinal associations between caregiver-child dyadic unpredictability, children's verbal abilities, and externalizing problems, and the moderating role of temperamental surgency. Participants were 235 families with young children (M_age = 2.97 years, SD = 0.38, range = [2-4], 55.3% female, ethnicity: 55.2% White, 21.3% African American, 16.2% mixed race). Mother-child dyadic unpredictability measured at Wave 1 was linked to lower verbal development over Waves 1 and 2, which was associated with greater increases in externalizing problems over Waves 1 and 3. These effects were particularly salient for children with high surgency. In contrast, father-child dyadic unpredictability was linked to greater verbal ability for children with low temperamental surgency, although this finding did not hold after controlling for the variability in child dysregulation during father-child interaction. Furthermore, findings revealed a curvilinear association between father-child dyadic unpredictability in association with the development of children's verbal ability. The present study has important implications for understanding unpredictability within parent-child interactions and its influence on child development. (PsycInfo Database Record (c) 2026 APA, all rights reserved).