‌William III 5Th Baron De and Maud (Matilda) De were married in a religious ceremony in 1169 in (Unknown), Eng.  They had thirteen sons and seven daughters, named Roger De, Robert De, Thomas De, William IV The Younger De, Giles De, Walter De, Reginald De, Hugh De, Henry De, Bernard De, Fulk De, Phlilp De, John De, Flandrina De, Matilda De, Joan De, Laurette De, Margaret De, Leuca De and Eleanor De.