Longitudinal Trajectories of Behavioral and Emotional Problems Into and During Adolescence for Individuals With Intellectual Disability

= 350) of children/adolescents with intellectual disability who were 10 years or older in Wave 1, 2, or 3 and under 16 years by Wave 3 of a longitudinal families study. Measures of child behavioral and emotional problems, parenting behavior, the parent-child relationship, and parent psychological distress were included. Using linear mixed modeling, behavioral and emotional problems declined slightly over time but remained high. Parenting behaviors and parent psychological distress did not affect trajectories. However, conflict (but not closeness) in the parent-child relationship was associated with increased behavioral and emotional problems over time. Higher levels of family financial hardship and an autism diagnosis were associated with increased behavioral and emotional problems. Child sex differences were also identified. Despite small improvements, individuals with intellectual disability exhibit high levels of behavioral and emotional problems into and during adolescence. Parent-child conflict may be an important focal point for interventions to reduce behavioral and emotional problems in young people with intellectual disability.