You might want to add the Magna Carta tag as Matilda/Maud Montgomery, daughter of Nicholas, is a Magna Carta profile.
It seems that two daughters of Matilda were betrothed in 1409 and 1410 respectively (see Richardson Magna Carta Ancestry: Carell p 477, and Gresley) which would suggest that Matilda was also a daughter of Nicholas Montgomery by his first wife Anne.