Lucas will eventually find out one way or another that sami slept with EJ, yes it was to save Lucas but he won't see it that way. He will just think of it as her lying to him. My thoughts he will probably be mad for awhile and leave her but over time continue sticking by her like he has over the years. I really hope it is Lucas's baby because maybe then do they really stand a chance. If not, and it does turn out to be EJ's that will be some twist.