If he could really be saved, and if she's willing, then it's fine by me but I don't think it's something she has to do after the abuse and neglect she went through. That's for me personally though, family abuse runs so deep, it's better to severe ties with them for your own sake. But as long as she feels (and is) safe to do things, feels "intact", and has the guidance, I believe it's fine. It's her well-being that matters, especially she's still so young and developing. Kanami is strong but also vulnerable. That's the only thing I'm worried about.