Jean De Beaufort 
Jean De was born about 1463. Jean De's father was Philippe I De Beaufort and his mother is Jeanne Le Josne De Contay. His paternal grandfather was Colart IV De Beaufort and his paternal grandmother is Isabeau D' Ollehain. He was an only child. He died on September 23rd, 1503.General Notes
SOURCES: LDS FHL Ancestal File # (familysearch.org)
"Ancestors/Descendants of Royal Lines" (Contributors: Manuel Abranches de Soveral, Reynaud de Paysac, F.L. Jacquier <Genealogy of Lewis Carroll, Justin Swanstrom, The Royal Families of England Scotland & Wales by Burkes Peerage; Debrett's Peerage & Baronage; Table of descendants French Canadian Genealogical Society; Families of Monfort-sur-Risle & Bertrand de Bricquebec; The Dukes of Normandy, XXXXI, Paul Leportier, Claude Barret; Irish Catholic Encyclopedia>, H.R. Moser <Burke Peerage>, L. Orlandini, O.Guionneau, L.B. de Rouge, E. Polti, A.Terlinden <Genealogy of the existing British Peerage, 1842>, L. Gustavsson, C. Cheneaux, E. Lodge, S. Bontron <Brian Tompsett>, R. Dewkinandan, H. de la Villarmois, C. Donadello; Scevole de Livonniere, I. Flatmoen)... http://geneastar.org.
They had a son named Philippe II De.