Socio-emotional bonding in early life is essential for mental development. Childhood adversity, such as abuse or social conflict, can lead to insecure attachment, increasing the risk of mental illnesses like mood disorders, addiction, and eating disorders. Oxytocin, a neuropeptide released during positive social interactions, plays a key role in bonding by activating receptors in the brain. Early life stress changes oxytocin system, which may result in stress susceptible brain. This project aims to investigate the role of oxytocin in development of the claustrum and its impact on social, emotional bonding and stress susceptible brain development. We will use mouse models with altered oxytocin signaling to study how disruptions in this process during early life affect claustrum development and behavior, focusing on the links between socio-emotional development and mental health outcomes.