Responses
No she is as far as I know, I think she just hates how her husband is and that it's in the bloodline, so she tries to get rid of it in her son by cruel means
I'm guessing not judging by the prince's reaction to "biological mom"
Maybe current duchess lost a loved one because of ML's obsessive yandere family and that's why current duchess hates the ML's bloodline?
Soo I'm guessing the current duchess isn't ml mum?