@Cheryl55,
Likely? Who knows?
Possible? Of course.
Or of course it could be that he is simply trying to be a good friend and help her out. Why don't you sit down with him and talk to him about it. Tell him you are concerned with the amount of time he is spending helping her. Let him know that it bothers you that he is spending so much time with her. See what he says.
Maybe the next time he gets a call that he is needed for something, ask him if you can go along. You know, just to chat with his friend while he is helping out. If there is nothing going on, he should have no problem with you tagging along.