Traumatic hip dislocation in children is an uncommon injury and constitutes an orthopaedic emergency. The case we present is a 3 year-old girl who dislocated her right hip posteriorly after her brother fell on her. The hip was promptly reduced with gentle manipulation and was immobilized with hip spica cast for 3 weeks. After removing the cast, protected weight-bearing was allowed for 3 weeks. Review at 6 months revealed normal examination and no evidence of avascular necrosis on radiograph. Most children have an excellent outcome after this injury. Avascular necrosis is a well-known and catastrophic complication of traumatic dislocation of the hip in children. Urgent reduction of the hip within 6 hours of injury reduces the risk of avascular necrosis.