Her profile states she is the daughter of Elisabeth de Broyes. Following that link, Elisabeth is the daughter of Hugues du Puiset and Louise, and the sister of Humberge who was married to Evrard.
The Overview for Isabel cites http://fmg.ac/Projects/MedLands/chamchalons.htm#IsabeauBroyesMSimon... which states she is the daughter of Hugues [I] & his [first] wife who was unknown.
Hugues married a second time to ELISABETH, daughter of ---. He states that possibly Elisabeth was the sister of Humbeline, wife of Erard [I] Comte de Breteuil.
If the citation given is correct, Isabel was the daughter of the first wife who was unknown, not Elisabeth the second wife.
Is there a citation for Alvide de Broyes who Is showing as a wife of Hugues "Bardoul" de Broyes, I ?