Maternal warmth moderates the link between physical punishment and child externalizing problems: A parent - Offspring behavior genetic analysis

Objective. We estimate the correlation between interviewer-rated harshness of maternal physical discipline and parent-rated child externalizing problems and test whether it varies as a function of maternal warmth or mother - child genetic similarity. Design. Using a parent - offspring behavior genetic design, we included 297 3- to 8-year-old children in 169 biological and adoptive families. Parents completed ratings of child externalizing problems and their feelings of warmth toward their children. They were interviewed about discipline, and global ratings of maternal warmth following a home visit were made. Results. The correlation between interviewer-rated harshness of discipline and parent-rated child externalizing problems was .27. However, this correlation was moderated by mothers' and observers' reports of maternal warmth: lower-warmth mothers, r =.36 to .40; higher-warmth mothers, r = .10 to .19. This pattern held for genetically related and unrelated (i.e., adoptive) mother - child pairs regardless of child age, sex, or age of placement. Conclusion. The link between harsh parenting and child externalizing problems is strongest when the mother - child relationship lacks warmth. This result is consistent whether the mother and child are genetically similar, thus ruling out passive gene - environment correlation as an explanation.