Shown in several secondary sources as daughter of Jacques Lord of Condé. Jacques did have a daughter Isabelle, but according to both Medlands and Etienne Pattou, this Isabelle married Jean I, Comte de Looz. As such, Isabelle who married Enguerrand de Fiennes is shown in the above sources as the sister rather than daughter of Jacques de Condé. 2
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4 May 1271, Westminster
Appointment of Nicholas de Yattindene to enquire what malefactors entered the manor of Isabel de Fednes of Wendevre when it was in the hands of the queen of England, and broke the door of a mill of the said Isabel there, and carried away the iron of the said mill and other goods to the value of 20l.
Calendar of Patent Rolls, Hen. III, vol. 6, p. 596
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Inquisition Post Mortem
470. Isabel de Fyenes
Writ (missing).
[Buckingham.] Extent made on Friday after St. Michael, 24 Edw. I. [1296]
Wendover. The manor (extent given) held in dower, of the inheritance of the heirs of Fyenes, of the king by knight's service.
She died on Sunday after the Nativity of the Blessed Virgin Mary, 24 Edw. I. William de Fyenes is right heir of the said manor, and of full age.
E. Ancient Extents, No. 79, m. 2. 3