Salvatore Bonanno was the first child of Bonanno crime family boss Joseph Bonanno and his wife Fay Bonanno (née Labruzzo). Bill first attended school in Brooklyn. In 1938, after his father purchased property in Hempstead, Long Island, he next attended school there after the family relocated. At age 10, Bill developed a severe mastoid ear infection. To aid in treating this ailment, his parents enrolled him in a Catholic boarding school in the dry climate of Tucson, Arizona.