If my brother and I are co-owners of our fathers estate what legal rights do I have?

He (my brother) has a total stranger staying there which we both agreed would NEVER happen.He's trying to hide this stranger from his wife (mid life crisis or something). But there's a completely untrustworthy lady(REALLY), staying in our parents home with ALL of our parents antiques and valuables. Can I take the police there and have her (and her dog) removed? I've got to do something quick, I noticed today that some items were already missing from the house. We agreed that no one would stay there unless it was him or myself from the very beginning, he won't even allow his wife on the premises, and complains every time my wife is there with me. (Now I see why).