Longo Baggins was an uncle of Bilbo, and married Camellia Sackville. When Longo's son Otho inherited the headship of the Sackville family through his mother, he became known as Otho Sackville-Baggins, and so founded that notorious family. Longo's relationship to Bilbo was important because Bilbo himself had no children, and so as the next in succession to Bilbo's father Bungo, Longo and his descendants stood to inherit Bag End. In the event Bilbo named a legal heir, Frodo, as his successor - much to the frustration of Longo's son Otho and Otho's wife Lobelia.