Rosemary Germaine (Rosie) Mole (b. 11 November 1982, during the bookThe Growing Pains of Adrian Mole) is the much younger sister of Adrian Moleand grows up to be his total opposite, although they do share quite a close relationship. By the age of 15, in Adrian Mole The Cappuccino Years, she has become a foul-mouthed rebellious vixen, modelling her appearance on Spice GirlEmma Bunton, and wears very short miniskirts. She becomes pregnant by a boyfriend named Aaron Michelthwaite, a fact she discloses only to Adrian, and orders a realistic baby-simulator doll to prepare herself for motherhood - although she later choses to have an abortion.
In the book Adrian Mole and the Weapons of Mass Destruction she is attending Hull University to study "Nanobiology" and has a boyfriend named Simon who is a drug addict. Once again, she confides her problems only to her brother: telling him that she has yet to begin her dissertation and needs money to support Simon's habit, whereas her parents believe she has finished a piece of original research and requires funds for a new printer. Whether or not she ever graduates is yet to be revealed.
Shortly after Rosie's birth, Pauline Mole's ex-lover Mr. Lucas claims to be her natural father. Pauline insists that Rosie is George Mole's child, and she is raised by the Moles, but the paternity issue is never definitively resolved.