Isabeau, dame de Montreuil - Her parents

https://fmg.ac/Projects/MedLands/HAINAUT.htm#_Toc120114381

2. FASTRE de Ligne (-after 1224). m BRIGITTE van Gavre, daughter of RASO Heer van Gavre & his wife Clarice Fastré & his wife had three children:

c) ISABELLE de Ligne (-after 1312) m GILLES "Rigaud" du Rœulx, son of EUSTACHE [IV] "Campulus" Seigneur du Rœulx & his wife Marie de Trith (-after 1299). Seigneur du Rœulx.