Traumatic brain injury (TBI), the alteration of brain function or brain pathology following external force, is common in children. TBI affects the sleep of victims, and poor sleep itself can impair recovery from TBI. Due to the developing brains of children, it is especially important to understand the complex interactions between sleep and TBI. Such understanding could lead toward optimizing recovery from TBI in children. Thus, here, we introduce the main issues in this field with a specific focus on the pediatric population and point out the important gaps in knowledge that need to be filled.