Early family attachments may determine the ease with which children form friendships and other relationships. Children who have loving, stable, and accepting relationships with their parents and siblings are generally more likely to form similar relationships with friends and playmates. First friendships are created when a child is about age 3, although preschoolers may play together before that age. Much like adults, preschoolers tend to develop friendships with children who share common interests, are likable, offer support, and are similar in sizes and looks. Childhood friendships create opportunities for children to learn how to handle anger‐provoking situations, to share, to learn values, and to practice more mature behaviors. Preschoolers who are popular with their peers excel at these activities. These children know how to be a friend, not just how to have friends. On the other hand, children who “tattle” or direct hostility toward their playmates tend to be less popular. In turn, aggressive children often have fewer friends, which fuels their hostility even more.