What do I do?

I’m a bit concerned and I don’t even know what to do. My fiancés ex, has been trying to contact him in previous months. She has thrown him in jail for domestic violence and stalking. He’s still on probation. Well they don’t talk, anyways she now adds my brother on fb. They have a no contact order, my fiancé and this broad. Well, what do I do? I have a 6 month old son with my fiancé and like what if my brother brings her to Christmas or something or telling her what we’re doing or whatever like I’m not sure what to think. The entire situation is crazy. What should I do?