https://en.wikipedia.org/wiki/Little_Brother
Relationships. Little brother, a male sibling who is younger in age - see birth order; Little brother, a boy supported by a surrogate "big brother", through an organization such as Big Brothers Big Sisters of America; Literature. Little Brother (Baillie novel), 1985, by Allan Baillie, a children's novel about life under the Khmer Rouge; Little Brother, 1996, a novel by David Mason