Federal Project Grant Award Summary

Arizona State University received a $100,228 Project Grant from the National Institute of Child Health and Human Development (NICHD) under the Child Health and Human Development Extramural Research program (CFDA 93.865), awarded December 1, 2026, with completion scheduled for June 30, 2028. The grant funds a longitudinal research study examining trajectories of sibling relationship quality in childhood and their associations with mental and physical health outcomes. The research employs latent growth mixture modeling to analyze sibling warmth and conflict across multiple developmental time points (ages 8-13 years) using data from the Arizona Twin Project, a diverse longitudinal study of twins and families in Arizona. The study investigates both genetic and environmental contributions to sibling relationship quality and their relationship to childhood internalizing symptoms, externalizing behaviors, and chronic pain conditions.

The deliverables include novel scientific findings on how sibling relationships evolve during childhood and mechanistic insights into the genetic and environmental factors influencing relationship quality. The research addresses a gap in developmental psychology literature by combining longitudinal, genetically-informed analyses with comprehensive assessment of both mental and physical health outcomes, ultimately generating evidence-based information to support prevention of mental and physical health challenges in children. The study fills a critical need for developmentally appropriate intervention targets by establishing the protective role of warm sibling relationships in childhood wellness.