Such characteristics include affection; kindness, love, virtue, sympathy, empathy, honesty, altruism, loyalty, mutual understanding and compassion, enjoyment of each other's company, trust, and the ability to be oneself, express one's feelings to others, and make mistakes without fear of judgment from the friend.
As children mature, they become less individualized and are more aware of others.
This figure rose to 78% through the fifth grade, as measured by co-nomination as friends, and 55% had a mutual best friend.
Coaching from parents can be useful in helping children to make friends.
Eileen Kennedy-Moore describes three key ingredients of children's friendship formation: (1) openness, (2) similarity, and (3) shared fun.
and others, Kennedy-Moore outlines developmental stages in children's friendship, reflecting an increasing capacity to understand others' perspectives: "I Want It My Way", "What's In It For Me?
According to Anahad O'Connor of The New York Times, bullying is most likely to occur against autistic children who have the most potential to live independently, such as those with Asperger syndrome.
Children with Down syndrome have increased difficulty forming friendships.
Various academic theories of friendship have been proposed, including social exchange theory, equity theory, relational dialectics, and attachment styles.
Although there are many forms of friendship, some of which may vary from place to place, certain characteristics are present in many types of such bonds.
Additionally, older adults in declining health who remain in contact with friends show improved psychological well-being.
Children with attention deficit hyperactivity disorder (ADHD) may have difficulty forming and maintaining friendships, due to a limited ability to build social skills through observational learning, difficulties attending to social cues, and because of the social impacts of impulsive behavior and a greater tendency to engage in behavior that may be seen as disruptive by their peers.