I don't think EC itself is contagious, but it could be possible that whatever is causing the EC is contagious, since it can be caused by fungal or bacterial infections. Neither of the two boyfriends I've had since I've had this have caught it from me, but maybe yours has a different cause. Are you sure they have EC? I mean ours is chronic peeling, they might just have some other stuff going on. Could it also be possible that your son and his mother have eczema of the lip, which could be hereditary? Just throwing stuff out there.