The Codex de Roda names "Sanzio Garsias et Arnaldo Garsies ac Gilelmo Garsies, ac domna Andregoto, seu domna Acibella, seu et ---" as the children of "Garsea Sanzoz" and his unnamed wife. The Genealogica Comitum Guasconiæ names "Sancium-Garsiam et Willelmum-Garsiam et Arnaldum-Garsiam" as the three sons of "Garsiam-Sancium Corvum", specifying that they divided Gascony between them. The cartulary of Auch records that "Garsiam Sancium Curvum" had three sons "Sancium Garsiam et Guillelmum Garsiam et Arnaldum Garsiam", specifying that Sancho succeeded in Gascony, Guillaume in Fezensac, and Arnaud in Astarac. His birth date range is estimated based on the birth date range estimated for his father, although his estimated date of death suggests that he was probably born towards the end of this range.
Comte de Gascogne. The Historia Abbatiæ Condomensis names "Sancius-Garsiæ" as brother of "Arnaldus…cognomento…Natus", son of "comitissa…coniux…Garsiæ Principis cognomento Curvi" who restored the convent of Condom, specifying that he received "Vasconiæ Principatum". Monlezun names "Sanche" as oldest of the three sons of Garcia, specifying that he succeeded his father in "la grande Gascogne qui comprenait les vicomtés de Lomagen, de Gavarret, de Tursan et de Bruillois".
The name of Sancho's wife is not known. 2
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