Board Thread:General Discussion/@comment-45.26.94.209-20160630203540/@comment-23.122.217.39-20160701221535

Considering how often genetics are a plot point (ex, Prim had to hide Ney's existence from her husband because the blonde hair gave away it was Arth's kid), I'd say it probably doesn't.

I'm not sure if this'll end up being the answer but Michelle's hair shade, and Nemesis' hair shade, are both considered "Elphe Green", and genetically similar enough that people like, say, Hanne and Heidemarie can pass as sisters. So it's possible that Nemesis inherited the hair color from the same part of the family that Michelle did (assuming she didn't just get it from her mother).