Parental Differential Treatment of Siblings and Adolescents' Health-Related Behaviors: The Moderating Role of Personality.

Youth who receive comparatively poorer parental treatment than a sibling are at risk for maladaptive behaviors in a variety of domains, but research has yet to examine links with adolescents' health-related behaviors nor consider how those links may vary based on adolescents' personality traits, namely conscientiousness and agreeableness. Two siblings (n = 590 adolescents; 53% female; Mage = 15.86, SD = 1.73) from 295 families reported on their differential conflict and closeness with their fathers and mothers as well as on their personality, sleep habits, exercise habits, and general health habits. Multilevel modeling revealed that, generally, the less conscientious adolescents had better health habits when they had comparatively warmer relationships with their mothers. Less conscientiousness adolescents may be less distressed by inequality in the family, and thus may experience positive effects of relatively better treatment.