WILLIAM DE ROUMARE, Seigneur of Roumare (near Rouen), son of Roger FITZGEROLD (c), by Lucy, "the Countess," was born circa 1096. [Complete Peerage VII:667, (transcribed by Dave Utzinger)]
(c) He [Roger FitzGerold] and Lucy his wife gave the church of Asgarby to the canons of Lincoln. His obit was kept at Lincoln on 15 July. He witnessed an undated charter of his brother Robert to le Bec, which charter is confirmed by an undated charter of Robert's nephew William de Roumare, who calls Robert his predecessor. Robert had Corfe and other estates in 1086 and was living in 1096. Roger and Robert were sons of Gerold "Miles Christi", who with consent of Robert his son and heir gave to the nuns of St. Amand, Rouen, the church of Roumare for the soul of his wife Aubreye, who d. 21 May. Among the witnesses are Radulfus frater Geroudi and Osbertus de Novoforo (Neufmarche), who also attest another grant by the same Gerold to St. Amand in the presence of William, King of the English. Gerold, the Seneschal witnessed charters in 1055, 1063, and 1066, and circia 1064 Duke William established Gerold "dapifer" as Castellan of Neufmarche. Gerold de Neufmarche is witness to a charter of William I dated Apr 1067. The appearance of Osbern de Neufmarche as witness to the two charters of Gerold "Miles Christi" mentioned above, when taken in conjunction with the fact that his descendants were Castellans of Neufmarche, establishes the identity of the two Gerolds.
Note: Apparently Roger was the younger son, while Robert, the elder, inherited the Normandy estates. I assume that Robert may have been son of an earlier Norman wife. William, Roger's son, apparently inherited Roumare from Robert, who may not have had issue; yet other descendants inherited Neufmarche?