 Eleanor's three sisters were Isabella de Braose, Maud de Braose, Baroness Mortimer, and Eva de Braose, wife of William de Cantelou.While Eleanor was a young girl, her father - known to the Welsh as "Gwilym Ddu" ("Black William") - was hanged on the orders of Llewelyn the Great, Prince of Wales for alleged adultery with Llewelyn's wife, Joan, Lady of Wales.Following the execution, her mother held de Braose lands and castles in her own right.