Purpose: Sleep problems are common in neurodevelopmental genetic disorders (NGD), with impacts on daytime functioning amplified in these individuals. However, despite their prevalence and clinical impact, correlates of sleep difficulties in this group remain poorly characterized. This study used a large cohort of individuals with several rare NGDs…

This investigation examines the spread of problem behaviors (substance use and delinquency) between twin siblings. A sample of 628 twins (151 male twin pairs and 163 female twin pairs) drawn from the Quebec Newborn Twin Study completed inventories describing delinquency and substance use at ages 13, 14, and 15. A 3-wave longitudinal actor-partner…