
Emerging adulthood is a transitional period of self-exploration and potential stressors, emphasizing the necessity for self-regulation. Sibling interactions play a pivotal role in the development of regulatory abilities as siblings provide a safe space to practice these skills. The role of sibling closeness and associated psychosocial development is not well understood as sibling interactions tend to decrease as emerging adults spend less time with family and more with new peer relationships. The purpose of this research is to explore longitudinal changes in sibling interactions and associated mental health in emerging adults across the fall and spring school semesters.