Family functioning and child participation are critical factors in recovery from traumatic brain injury (TBI) and academic and social outcomes. Using mixed methods, we investigated these factors in children who experienced early childhood TBIs and then entered formal U.S. schooling. Caregivers completed interviews and scales of family functioning and child participation. Their scores did not reflect problematic family functioning, but showed participation across settings was below average. Themes from interviews included: (1) early childhood TBIs can affect family functioning even years after the injury; (2) learning, academic, and social-emotional issues impact participation and family functioning following early childhood TBI; and (3) appropriate supports and accessible environments are critical for both family functioning and child participation across settings. Mixed methods analyses indicated convergence, divergence, and expansion between qualitative and quantitative results. Results enhance our understanding of challenges encountered after early childhood TBI and provide directions for future interventions.