If you end up killing one of the characters in the end of GTA V, is there a way to get them back?

So, I decided to kill Trevor because I thought "Deathwish" meant that Franklin would die. It does not, nobody but the evil buttholes die that torment all three playable characters all game. I did not know this at the time, and only found out after I looked it up on YouTube.

I tried to play the mission in the replay missions section, but my PS3 crashed during it (Weird, as the game played flawlessly until I did so), so I lost the will to try that long-*** mission again. But, if you do play and complete it, does that give you all the characters back? Because I finished the game leaving most of Trevor's side missions undone compared to the other two, and its a pain in the butt to drive all the way out to the countryside having nobody lives out there but Trevor.

Thanks in advance.