I know she's warry of the Duke because she sees him as the cause of Ain becoming evil, but as she becomes aware of the "education" standards of the house, I hope she realizes that the Duke also is a product of that upbringing.
You can do it Duke! You might just begin to grow on her now, she is a tiny little bit less wary of you and is trying to make it work!
As for relationship with your son, well, that's another story ^^;