Guiraude was married to a distant cousin, Arnaud Dat, seigneur de Mixe and Ostabarret, and with the death of her brother, vicomte Pierre Arnaud, without issue (c. 1120), she and her husband succeeded to vicomte. Their marriage had reunited the two branches of descent from Arnaud Loup, the first vicomte of Dax, who died prior to 1020.