What can we do if we found out a kid isnt ours, shes a threat to our lives please help?

i just asked a question earlier but forgot to add additional details we just found out a kid isnt my husbands and she is a threat to our lives, she smears poop on our bathroom steals from us lies like no other, hurts our animals an even attempted to kill our kitten but thank god we were able to stop it and she has threatined to hurt our new baby, bfor our baby was born we put this kid in counsiling, therapy, and we would love her try everything in our power to help her and everything was a game to her, i spend thousands of dollars trying to help her an none of it worked and even though we gave her everything and love an attention bfor and after baby was born she would continue destroying our home an now we lock our bedroom door at night with our pets an our baby in there with us b cuz we fear for our babys life, we took a dna test come to find out shes not biologically my husbands, we dont want her here no more we have to protect our baby and us from her, we have tried so hard and just cant put our family at risk any more but shes been in our lives for a few years already so do we legally have to keep her or can we make her mom take her and will we have to pay child support if we bring the paternity test results to the courts attention plz help wut should we do,we arnt bad ppl at all weve done all we can, and honestly if she was a good kid it wouldnt matter if she was either of ours we would still take her in an love her as our own but this isnt the case and its a horrible situation and i need to protect my own helpless new babygirl