Children who feel poorer than their friends have worse mental health than those who are or who feel equal or richer than their friends. In a new study published in the Journal of Child Psychology and Psychiatry, researchers from the University of Cambridge analyzed perceived economic inequality within friendship groups of almost 13,000 11-year-olds. They found that children who felt poorer than their friends had lower self-esteem, more anxiety, more issues with anger and hyperactivity, and were more likely to be bullied. On the other hand, the children who felt richer than friends were three to five percent more likely to bully others.