van de Pas: "William was only twelve when his father died. The wardship of William and the de Braose lands were granted by King Henry III to Peter des Rievaux. On his fall in 1234, these custodies were passed on to the king's brother, Richard, Earl of Cornwall. When William came of age he took control of the Braose lands in Gower, Bramber and Tetbury. He confirmed the grants made by his father of the rents of cottages in Tetbury to the priory at Aconbury, founded in the memory of Maud de St.Valery by her daughter Margaret. These cottages still existed in 2002. William was plagued throughout his life by a series of legal battles with his female relatives.

William de Braose's first wife was Aline de Multon, daughter of Thomas de Multon and Maud de Vaux. William and Aline became the parents of one son. By his second wife Agnes de Moeles he also fathered only one son. William de Braose married about 1271 Mary de Ros, daughter of Sir Robert de Ros, of Helmsley, and Isabel d'Aubeney. William and Mary became the parents of three sons and one daughter."