
This isn't normal behaviour, at 3 months. Could be because she was a singleton she didn't have a 'normal' early start in life but my singleton bitch never attempted to do this I have to say. I think, 'hard' or not, you can only keep her separated from the other bitches when you are not around, and be ready to pounce on her the moment she tries this, when you are. Hopefully she will grow out of this - especially if she's making mum sore. Leaving a situation like that isn't fair on mum, by a long way - and indeed mum's milk needs to dry up, so continually nursing, or attempting to, isn't going to help that! Again more reason to stop this.