To take one line of thought, Sam can’t miss what he’s never had.
On the other hand, he’s also going to be a teenage guy, and if I know teenagers in general (and Sam in particular, as we saw the huge streak of independence he has in the show), he’s not going to want to be carried everywhere. He’s going to find a way around it, just like he did in Brothers Apart, and just like he does in Brothers Asunder.
Brothers Apart 