Good quality sleep health is fundamental for children’s optimal developmental outcomes. Children with a traumatic brain injury, one of the most common adverse outcomes in childhood affecting 1 in 5 by age 15-years, are at increased risk of experiencing sleep problems. Sleep problems in children adversely affect their behavioural and emotional adjustment, with elevated risks of educational under-achievement, negative social outcomes, and increased parental stress impacting the child parent-relationship. There is limited research investigating the types of sleep problems experienced by these children, with the majority of research focused on adults. The proposed study will investigate the types and forms of sleep problems in children with a brain injury between ages 2 and 12-years alongside their psychosocial outcomes. There is an urgent need for understanding sleep problems following childhood brain injury in order to develop clinical interventions specifically targeted to improve the sleep health and behaviour of these children.