Isabelle De Trichasteaux 
Isabelle De was born about 1237. Isabelle De's father was Jean De Til-Chatel and her mother is Aluys De Vergy. She had a half-sister named Beatrice De.General Notes
SOURCES: "Ancestors/Descendants of Royal Lines" (Contributors: Reynaud de Paysac, H.R. Moser <Burke Peerage>), O.Guionneau, E. Polti, A.Terlinden <Genealogy of the existing British Peerage, 1842>, E. Lodge, and Aurejac)
Isabelle De and Guillaume De were married in a religious ceremony in 1252. They had a son and a daughter, named Eudes V De and Alix De.
