Wise teachers of infants and toddlers know how concerned, helpful, empathic, cooperative, and friendly--that is, how prosocial--very young children can be. Teachers see older infants crawl or toddle over to "friends" arriving later in the morning and greet them as if they had not seen them in weeks. Teachers and families know that these young children care and think about others and form strong, loving relationships with both adults and peers. Recent research, including brain research, shows that young children are capable of being prosocial, caring, and loving, but need adult support to maximize these competencies. In this article, the author shares information about how important the first three years of life are for infants' and toddlers' development of social competence. These years form the foundation for successful relationships throughout life. Her goals are to increase readers' appreciation for infants' and toddlers' remarkable relational capacities and to recommend developmentally appropriate practices that can improve the quality of peer experiences for young children in early care and education settings. Throughout the article, the author highlights the importance of quality, caring adult-child relationships for young children as they negotiate the joys and challenges of peer relationships.