My mother in law has a dog that is violent to humans and her new dog. I don't feel safe going to her house anymore, or bringing my daughter there! What would be the best possible course of action in this situation?

My mother in law owns a beagle/lab/chow mix who is about 2 years old. Recently, she got another dog from the local shelter and was told by the shelter that she would have to neuter her chow mix in order to keep her new dog. The chow mix was neutered, but became increasingly violent towards humans and the new dog, where he had not been before. He DID calm down about 3 weeks after the operation.

Two days ago, a friend of ours walked into the house with me, and the chow mix bit him! It didn't break the skin, but if our friend hadn't been wearing a jacket it would have. My MIL loves this dog, and normally he's good, but we have a 3 month old, and I'm afraid that he might attack her next! Plus, my MIL defends the dog saying he did nothing wrong, and her other dog (a lab/pit mix) is untrained and has attempted to attack me, my husband, and my baby! I don't feel safe going to her house anymore, or leaving my daughter there! What would be the best possible course of action in this situation?