A little confused ...*spoilers*
Since Sam was jumping back into the past and present, what happens to the versions of himself during those times? He became them and they became nothing?
If that's the case, so can it be said that ever since he rescue his sister, Jenna, from dying in the fire, every version of her in the past is actually the current her and not the "past" her anymore?
Sorry, I don't even know if I am making sense anymore :)