I’ve completed my research on the Brabant family tree, focusing particularly on the time period from 1165 to 1235 (those are the dates of the birth and death of Duke Henry I, respectively). In between that time, I’ve managed to line up all the events that would’ve personally affected Henry, his wives Matilda and Marie, and their issue.
I am now completely convinced that FK’s writers Did Not Do The Research, and that a certain part of the homecoming scene in BMV is a historical “oops!”. (Hey, it wouldn’t be the first time…) Therefore, I will have to retcon “Mother”, possibly replacing her with a sister (Marie, Adelaide, Margaret or Matilda) or Matilda’s niece (also named Matilda), in order to make it more historically accurate.
There are way too many Matildas and Maries in the Brabant family tree. But you gotta admit, Duchess Matilda must’ve been a pretty awesome chick to have her youngest daughter, her niece and a granddaughter named after her.