Abstract The overarching goal of this proposal is to identify CVH trajectories from birth through age 20 among a diverse cohort of 7,000 children and their families who already have clinical phenotyping to which we will add detailed behavioral data and follow them longitudinally. Using an innovative study design for a pragmatic cohort utilizing technology-enabled data collection we will recruit a diverse cohort of children from a city-wide electronic health record (EHR) system in Chicago. Parents/children will complete a developmentally appropriate and clinically feasible set of online surveys and questionnaires to assess behaviors and lifestyles that will be linked with their EHR data already being used in a prior study. After two years we will re-assess each child's CVH. Our innovative accelerated longitudinal study design (ALD) will allow us to define CVH and create trajectories for a diverse group of children from birth through age 20 all within the 5 years of this grant. These trajectories will then be used to create a novel “CVH growth curve” ready for use in clinical practice. Our team has the unique expertise to complete this study including already having the EHR data for children across Chicago, expertise in cohort recruitment and retention as well as inclusion of leading experts in studying CVH among children. The findings from this study will be critical in targeting prevention strategies to high-risk children and critical periods during the life course in order to prevent the loss of CVH in childhood and preserve and promote CVH across the life course. We will develop a clinical tool, CVH growth curves, that can be directly translated into clinical care and will inform prevention efforts. Our specific aims are as follows: Specific Aims: 1. Identify CVH trajectories from birth to young adulthood within a diverse cohort of participants (n=7,000) across the city of Chicago 2. Identify predictors of CVH trajectories from birth to young adulthood within a diverse cohort of participants including a broad range of markers of resilience and vulnerability 3. Develop an accurate and generalizable Cardiovascular Health Growth Curve for use in clinical care to target prevention to children at high risk of declining CVH and subsequent CVD