Eustache I De Conflans 
Eustache I De was born about 1160. Eustache I De's father is Hugues De Conflans. His paternal grandfather was Engelbert De Brienne and his paternal grandmother is Adeline X. He was an only child. He died after 1224.General Notes
Seigneur d'Estoges
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, H. de la Villarmois, I. Flatmoen, G., N. Danican, Kepklian, E. Visseau, /B. Devoucoux, P. Pluchot)... http://geneastar.org.
They had a son named Eustache II De.