The number of children in the United States exposed to a traumatic event each year exceeds 4 million. Depending on the severity, frequency, nature, and patterns of traumatic events, at least half of these children are expected to develop significant neuropsychiatric symptomatology. Research on outcomes of children witnessing a sibling s traumatic injury are unknown. This longitudinal, repeated measures study will investigate the effects of a sibling witnessing a traumatic injury and the mediating effect of the parent-child relationship on the sibling's behavior. This study is designed to build on Dr. Youngblut s study of pediatric head trauma. Fifty siblings that witnessed and a comparison group of fifty siblings who did not witness the child's injury will be recruited from two midwestern hospitals through the families of the larger study. Other inclusion criteria are: must be a sibling of the head injured child, between the ages of 6 and 12, living in the same family as the injured child, understand spoken English, and not hurt in the injury event. Exclusion criteria are: no other traumatizing event in the last year and no preexisting psychiatric problems. A conceptual framework for this study is based on the two major components of the Neuman Systems Model: stress and the reaction to stress. Data will be collected in the family's home at 2 time points: T1 - 2 weeks after the injured child's injury, T2 -3 months after hospital discharge of the injured child. The data will be collected on the parents and the sibling. The proposed study will provide data on the relationship of appraisal of the event for the child, parental mental health, and parent-child relationships on behavioral outcomes. This study is designed to identify factors that affect the stress response of the sibling.