A. Summary of parent grant There is a widespread recognition that mental health is often neglected, under-resourced, and underfunded, particularly in low- and middle-income countries (LMICs) 1, 2. Experiencing traumatic events as a child is often linked to mental health problems and higher levels of stress reactivity and impact one's entire ecology with long-term intergenerational consequences 3. The treatment gap, is more than 50% in all countries and can be as high as 90% in the least resourced countries 4. Sierra Leone is one of many low and middle-income countries (LMICs) that have encountered challenges in providing mental health services to their population, particularly children and adolescents 5-6. This has been compounded by the country's experiences of war and the Ebola outbreak. The parent grant for the proposed supplement is a mixed-method, longitudinal study evaluating the long-term effects of war and trauma on parents and their relationships with their children, families, and communities. Previous studies have noted the limitations of relying on self-reported family dynamics in post- conflict settings, including Sierra Leone 7. There is a need for observational techniques and instruments that are context-specific, current, biologically based, and tailored to fathers to supplement self-report methods. The findings from this study will inform the development of decision-support tools for lay-worker-delivered prevention models to support family interventions to address specific needs, based on the family's distinct pattern of risk and protective factors. Specific Aims of the parent grant: The primary aims of the parent grant are as follows: (1) Investigate the biological embedding and long-term mental health consequences of war-related trauma in a longitudinal sample of war-affected youth who have become parents (N=394). (2) Examine associations between parental war-related trauma exposure, mental health, and biological and physiological indicators of emotion, cognition, and social functioning in offspring aged 7–24 (N=410). (3) Identify and examine how modifiable risk and protective factors operate to identify priority intervention targets to improve the physical and mental health of war-affected children and to develop screening tools to identify families at risk.