As ABibleStudent says, go see him face-to-face. Don't acknowledge the text any other way except a personal visit. How does he know you even received the text otherwise. I assume he doesn't go to your hall so you wouldn't have heard any announcement about it. Just go over and see him and maybe bring something for his little baby and set aside some time to spend with him. If he wants to talk to you about his situation you could say "i thought it was a spam text" or just say it must not have gotten delivered (that happens sometime) and just listen to what he has to say. That way you can gauge how he feels and since you are already there to see him and bring something for the baby you can continue asking about how he and his family is. As others have said, don't text him and calling is really not enough to get proper feedback or give proper comfort to someone in his situation. At least that is what I would do...and then see how things go after that.