Yves I De+ Beaumont-Sur-Oise 
Yves I De+'s father is Yves De+ Beaumont-Sur-Oise and his mother is Gisele De+ Chevreuse. He is an only child.General Notes
SOURCES: LDS FHL Ancestal File #
"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>, 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, C. Donadello) http://geneastar.org.
He had a biological son named Yves II De+.