Over 75% of all adolescents will experience the death of a close friend by the time they reach college age, and 3 million children will experience the death of a parent by the age of 18 (or the equivalent of one child in every classroom). Bereavement is associated with increased risk for psychopathology, even though available clinical trial data suggest that interventions are effective. Extending these early clinical trial findings to children and adolescents is hampered by the limited understanding of temporal patterns of post-loss psychopathology, as well as the joint effects of genetic liability, developmental timing, cognitive ability, psychosocial variables, and environmental exposures. This project will focus on addressing these knowledge gaps by investigating pathogenic processes in post-exposure psychopathology among youth, ultimately pointing to candidate preventative and intervention approaches.