The Mating of Millie (1948)

Self-sufficient in life and successful in business, prim and proper Millie McGonigle wants just one more thing, a child. When she asks to adopt orphan Tommy Bassett, but learns that she will first have to have a husband, Millie turns to her neighbor, Doug Andrews. Though he has no interest in marriage, Doug offers to help Millie find a husband by transforming her into a beautiful and exciting woman, one who catches the eye of two eligible bachelors, including the orphanage's president.