Robert III de Brenne - Medieval Lands says that line can be extended to another Rboert

Also the Robert married to Isabelle should be IV.

https://fmg.ac/Projects/MedLands/anjounob.htm#_Toc492564517

1. ROBERT [III] de Rochecorbon, son of --- (-after 1179). Seigneur de Brenne. ... m ---. ... Robert [III] & his wife had two children:

b) ROBERT [IV] de Brenne (-1227, bur Tours) ... m ISABELLE de Pocé ... Robert [IV] & his wife had two children:

ii) GUILLAUME de Brenne (-before [1251/58]). Seigneur de Brenne ... m as her first husband, MATHILDE de Mirebeau