National Brother’s Day

About 80% of Americans grow up with at least one sibling. For most of them, the sibling relationship will be the longest of their lives — outlasting relationships with parents, spouses, and often children. It begins before either person can form memories and, in many cases, doesn't end until one of them dies.

National Brother's Day, observed on May 24, was created by C. Daniel Rhodes of Alabama in honor of her own brother. The observance recognizes a bond that developmental psychologists consider among the most formative in human life: siblings are a child's first peer group, the first people they learn to share with, compete against, and forgive.

C. Daniel Rhodes created National Brother's Day to honor her own brother. Rhodes, from Alabama, wanted a dedicated day that recognized the specific bond between brothers, complementing Mother's Day, Father's Day, and the existing Brothers and Sisters Day (May 2). The observance is most commonly dated to the early 2000s.

The day exists because the brother relationship occupies a particular space in human development that researchers have studied extensively. Siblings are typically a child's first peer group. Before school, before friends, brothers and sisters are the people a child first learns to negotiate with, argue with, and reconcile with.

What research says about siblings

The American Psychological Association identifies sibling relationships as among the most enduring and influential in a person's life. Older siblings significantly affect younger children's social, psychological, and cognitive development. Younger children are more likely to imitate and consult an older sibling than a same-age peer.

Positive sibling relationships are associated with higher self-esteem, better social competence, and reduced depression in adulthood. Chronic sibling conflict, on the other hand, is linked to anxiety and lower self-worth. The quality of the relationship, not its mere existence, determines the outcome.

Birth order: what's real and what isn't

Alfred Adler proposed in the early 1900s that birth order shapes personality. Firstborns were achievers and leaders. Middle children were peacemakers. Youngest children were sociable attention-seekers. The theory became one of the most widely repeated claims in popular psychology.

Modern research tells a different story. A 2015 study published in the Proceedings of the National Academy of Sciences, analyzing data from over 20,000 individuals, found no significant effects of birth order on personality traits like extraversion, agreeableness, or conscientiousness. Firstborns showed a slight advantage in measured intelligence, but the effect was small. The popular stereotypes persist despite the evidence.

Brothers who changed the world

The history of brother partnerships argues for the power of complementary skills within a shared origin. Orville and Wilbur Wright combined theoretical thinking with mechanical talent to achieve powered flight. Jacob and Wilhelm Grimm collaborated on folk tale collections that defined an entire genre of literature. Walt Disney imagined worlds while his brother Roy built the business to pay for them. Maurice and Richard McDonald designed a fast-food system that Ray Kroc scaled into a global empire.

In each case, the brothers brought different strengths. The relationship worked not because they were alike, but because they weren't.