Young children’s relationships (2–6 years) tend to be low in intimacy. Relationships are either between two people of unequal standing (e.g., parent and child) or two equals who do not have emotional closeness (e.g., two preschoolers playing with the same toys). Children’s main task is to learn to delay gratification in order to maintain relationships over time. Children must learn to take turns, to share belongings, and to follow rules so that everyone can enjoy play. Some children will develop imaginary friends with whom they will “practice” these skills.

      Slightly older children (6–9 years) begin to establish relationships with peers. Sullivan saw these friendships as critical for all later relationships. In the classroom and on the playground, school-age children decide which peers they like and dislike. By accepting another child into one’s play group, the child is saying, “I like and value you.” Acceptance establishes a sense of self-worth in children.

      Sullivan described preadolescence (9–12 years) as a “quiet miracle” in which children begin to develop close relationships with one or more “best” friends. These friends act as a source of security and support in times of trouble. Sullivan believed these relationships can begin to foster love, a feeling that occurs when another person’s happiness and security becomes as important as the happiness and security of oneself. Sullivan believed that loving relationships allowed preadolescents to share their feelings without fear of rejection or humiliation and to take risks in exploring their identities and values.

      Adolescence (≥13 years) begins with puberty and ends with the establishment of loving and mutually supportive relationships with others. Sullivan saw early adolescence as a time of insecurity and self-doubt that can be managed through the emotional support of peers. In time, however, adolescents use their increased capacity for intimacy to initiate deep friendships and romantic relationships. Part of this transition involves viewing partners not as objects designed to gratify their needs but as autonomous individuals with their own identities, values, and intrinsic worth.

      Peer Acceptance and Rejection

      The formation of relationships depends on cognitive, emotional, behavioral, and social factors (Hay, 2016; Prinstein & Giletta, 2016). First, the ability to form friendships depends on children’s cognitive development. Young children must be able to attend to the activities of others, imitate others’ actions, understand cause-and-effect relationships, and have basic competence with language. Children with autism, communication or learning disorders, and developmental disabilities may have trouble gaining acceptance from peers because of deficits in these areas.

      Second, interpersonal relationships depend on the ability to accurately interpret others’ emotions, the capacity to regulate one’s own emotional expression, and the ability to empathize. As we have seen, youths with autism have difficulty understanding emotions and showing empathy. Children and adolescents with mood disorders also typically have problems with emotion regulation. Irritability, sadness, or social withdrawal can compromise their relationships with family and friends.

      Third, children must be able to regulate their own behavior to make and keep friends. Children with ADHD and other disruptive behavior disorders are often rejected by peers because of their aversive, high-rate, or aggressive actions.

      Finally, children need adequate social skills to form intimate relationships with others (McGinnis, 2011a, 2011b). These skills include knowing how to introduce yourself to a stranger, how to avoid a fight with a friend, and how to cope with social stress or peer pressure. Inadequate social skills can lead to peer rejection. Some peer-rejected youths develop depression and other mood problems, whereas other rejected youths associate with deviant peers who introduce them to antisocial behavior.

       Review

      How Do Other Social–Cultural Factors Influence Development?

      Proximal and Distal Risk

      Until now, we have focused chiefly on the immediate causes of childhood disorders. These causes include the child’s genotype, brain structure and functioning, learning experiences, thoughts and feelings, and relationships. These immediate determinants of children’s functioning are often referred to as proximal risk factors because they can directly affect children’s well-being. For example, a genetic disorder can lead to low intellectual functioning, whereas exposure to harsh, authoritarian parenting can contribute to children’s oppositional and defiant behavior. The overwhelming majority of research addressing the causes of child psychopathology focuses on proximal risk factors because they are typically the easiest to study (Tolan, 2016).

      Researchers have increasingly turned their attention to other, distal risk factors for child behavior problems. Distal risk factors are social, cultural, and broad environmental influences on development. One important distal risk factor is socioeconomic status (SES). Children from low-SES families are at increased risk for developing behavioral and emotional disorders compared to youths from middle- and high-SES backgrounds. Other distal risk factors include family structure (e.g., single-parent families), neighborhood quality (e.g., population density, crime), and broader social–cultural values (e.g., importance of school, family, or religion; Wadsworth, Evans, Grant, Carter, & Duffy, 2016).

      Distal risk factors, like poverty and neighborhood disadvantage, can directly influence child development. For example, infants and toddlers who ingest lead are at risk for developing behavioral and learning problems. Typically, youths are exposed to lead from paint that flakes off the walls of older homes. Children from low-SES families are disproportionately exposed to lead-based paint because they often live in older, more dilapidated homes. Consequently, rates of lead poisoning, and subsequent neurological damage, are greatest among youths from low-SES families (Jennings & Fox, 2015).

      Distal risk factors can also indirectly influence child development. For example, the degree to which parents argue over financial concerns predicts the extent to which they use harsh discipline with their children. Their harsh parenting behavior, in turn, predicts the emergence of their children’s behavior problems. In this case, financial stress contributes to children’s behavior problems indirectly, by increasing problematic parenting behavior (Lee, Lee, & August, 2012).

      Bronfenbrenner’s Ecological Systems Theory

      Perhaps the most influential and comprehensive explanation for the way