Ray Phair in his July 1999 article “Who were the parents of Gilbert de Gant?”, now on the Rootsweb medieval site at: www.rootsweb.com/~medieval/gant.htm, suggested that Gisla (ex Keats-Rohan’s Domesday Descendants) was in fact Gisele whose sister was Otgive, wife of Baldwin IV count of Flanders and whose father was Frederick count of Luxemburg.  This gave her son Gilbert, apparently, Carolingian descent.
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