Abstract
This study used data from the Co‐Space Study to examine children and adolescents' mental health trajectories over 13 months of the pandemic and whether family, peer, and individual‐level factors were associated with trajectory membership. We found that most young people adapted well and experienced low stable symptoms, but nearly one third experienced high stable or increasing mental health difficulties. Young people with complex needs and parents with higher psychological distress were particularly vulnerable to high mental health difficulties while those with positive peer relationships were less vulnerable. This study offers insight into potential factors that can be addressed using targeted interventions to improve the wellbeing of parents and young people in the event of future lockdowns and school closures.