Social-emotional difficulties and unhealthy lifestyle behaviors in children are both prevalent in the US, tend to co-occur, and share underlying risk and protective factors. Difficulties in either domain are associated with a range of adverse short- and long-term health outcomes, such as mental health disorders, substance use disorders, academic problems, and chronic health conditions. Child social-emotional difficulties and unhealthy lifestyle behaviors may be exacerbated by major family stressors, such as parental trauma history and mental health difficulties, parental HIV, parental substance misuse, economic strain, and racial discrimination. Family stressors may contribute to children’s well-being indirectly by exacerbating parenting stress, impeding parents’ self-regulation, and hampering their parenting efforts. Several preventive interventions are effective in improving parenting skills and promoting children’s well-being. However, families dealing with major stressors face significant barriers to accessing and reaping the benefits of these preventive interventions, in part because of a limited focus on parents’ own stress and coping strategies. Further, these interventions typically target child outcomes in either social-emotional or healthy lifestyle domains, but not both concurrently. The purpose of this study is to assess the feasibility, acceptability, and preliminary efficacy of a parent-based preventive intervention targeting parental self-regulation, stress reduction, and positive parenting, to promote child social-emotional and lifestyle health, among parents who have a child aged 3-9 and who are experiencing major stressors, such as history of trauma, mental health difficulties, HIV, racial discrimination, substance misuse, and/or financial strain. This pilot feasibility study is being conducted with a sample of n = 60 families randomized to a family stress-oriented preventive intervention or waitlist control. Aims include examination of: (1) feasibility, acceptability, and implementation processes of the parent-based preventive intervention via mixed methods, and (2) preliminary efficacy of the preventive intervention regarding child well-being (mood, social competence, sleep, screen time, physical activity), positive parenting, and parenting stress and self-regulation. This project is innovative in that it seeks to concurrently promote the dual prevention of children’s unhealthy lifestyle behaviors and social-emotional difficulties, emphasizing parental self-regulation and stress reduction in the context of a parenting support program. This line of research ultimately targets prevalence reduction for children’s social-emotional and health-behavior difficulties by addressing parent stress, promoting parental self-regulation, and bolstering parenting efficacy.