!The Roll of Battle Abbey says William the Conqueror was Gundred's father instead of Gherbod.
FOSTER LINE - 26th ggrandfather
!Advocate of the abbey of St. Bestin, at St. Omer. His liaison with Matilda of Flanders, prior to her marriage to William, produced Gundred. [Magna Charta Barons, p. 80]
!A valiant Fleming who was an Earl of Chester prior to the Conqueror's invasion. He soon departed into Flanders, where he was detained a prisoner and in his place in Chester, the Conqueror put his nephew Hugh d'Aurange/Hugh Lupus. [The Bruces and the Cumyns, p. 512]
This source says he was a son of Queen Matilda during a clandestine marriage prior to her marriage to William. William's treatment of him following the invasion would more likely support that he was a former lover of Queen Matilda. [Falaise Roll, p. 52]
Hereditary Advocate of St. Butin at St. Omer; Earl of Chester; father of Gundred who m. William I de Warenne. [Charlemagne & Others, Chart 2958]