Nip/bite her back immediately when it happens, (gently of course) you'll give her a shock, then gently physically remove her to her room with no toys or distractions, a 5-10min timeout to think of her actions, and apologies on exiting. rinse and repeat to reinforce that behaviour is not acceptable in your care.
I know that sounds hard, but reasoning with young kids very rarely works, they respect discipline they can understand there boundaries.
Best wishes zipper, please dont think im horrible, have found this strategy works when consistency is kept. They get it before they acknowledge it, so to speak, and will push you.
