Divorce

Hi there-

I have a question. My sister is in the process of separating from her husband. Both have been unfaithful and quite frankly they are both a mess right now. Her husband has drug issues and recently went to rehab-he refuses to leave the house, so she signed a lease on an apartment. She doesn't want to uproot the kids-and she really wants to stay in the house and have him go to the apartment. He is refusing.

So-my question. She is convinced that she can't legally make him leave. What happens when someone files for divorce? Can a temporary order be made about the house? While neither are stellar parents, I would think the children's best interest would be best served by him leaving and her and the kids staying in their home. Does anyone know how this might work?