In the highly divisive sequel to The Last Of Us, there were some pretty big changes to the main character's personalities. Some of these come because of the changes to various huge story events, but others just happen with age and a different living situation.
Ellie and Joel have settled down with Tommy in his little village, and things are good for the most part, and Ellie's now all grown up. That being said, not everything is as idyllic as it seems when a mysterious stranger shows up to get revenge on Joel, and Ellie changes immensely as a result.
10 Ellie: She's A Bit More Rebellious
When we first meet Ellie, there's really no indication that she isn't already a bit of a rebel, but the more time we spend with her, the more it seems apparent that she marches to the beat of her own drum, no matter who it upsets. She's usually justified in the way she's acting, although a lot of people don't see it that way. She definitely seems like a grown-up version of the foul-mouthed kid we met in the first game.
9 Joel: He's More Fatherly
When we're introduced to Joel in The Last Of Us, he's not particularly excited to be transporting the new cargo he's saddled with. He's the kind of type who would rather be smuggling guns in and out of the city, and not so much a child. That being said, he gets closer and closer to Ellie and is incredibly hurt when Ellie is upset with him and refuses to talk for a while.
8 Ellie: She's More Sociable
For most of the time we spend with Ellie in the first game, she's pretty tight-lipped with people she meets, including the leader of a civilization of cannibals we meet. She occasionally makes small talk with Joel, but at first, she really doesn't go out of her way to make conversation.
Later on, we see that she's adapted pretty well, had romantic relationships, and tons of friendships.
7 Joel: He's Less Cynical
Joel isn't exactly the most hopeful person in the world, especially since he's watched his entire world fall apart before we met him, being born and living well before the infection originally took place. He seems to think the way it was handled was awful, he doesn't ever see a meaningful recovery, and he doesn't really even care to exist. Later on, we see that he might have actually found happiness in his new life.
6 Ellie: She Learned Guitar From Joel
When we're following Ellie and Joel around in the first game, Joel admits to Ellie that before all of everything went to hell, he desperately dreamed of being a singer, which was a reference to the fact that his voice actor is a musician. When we start The Last Of Us II, it's revealed that Joel finally did teach Ellie guitar, and she's just about as proficient at it as he is, as evidenced in a few sequences where she plays.
5 Joel: Gone Is His Violent Reputation
Joel had quite a reputation pretty much around the world for being a bit of a cut-throat kind of guy.
While most of the time this was presented pretty much just to say that Joel was a survivor, it's hinted that he and his brother Tommy both have some pretty violent pasts. When we see Joel later on in the second part, he's left that behind for a peaceful existence in town.
4 Ellie: She Distrusts Joel
Unfortunately for Ellie and Joel, they had a bit of a falling out, but this happened for good reason. Joel made a call that was much bigger than himself, and he ended up paying the price for it. He did what a lot of people would probably do in his place, saving his newfound daughter rather than the world. He decided to lie about it to Ellie, and as a result, they became estranged.
3 Joel: He Never Got Closure
While Joel and Ellie's relationship had gotten rocky more than a few times, nothing drove a wedge between the two of them more when Ellie found out about the sacrifice he refused to make.
He basically threw away the whole mission for her life, and then got killed as revenge before they ever got the chance to really talk about it. Ellie must feel pretty awful about it, but there's nothing to do now.
2 Ellie: Her Innocence Is Gone
In the first game, Ellie isn't necessarily inexperienced or unfamiliar with the lot she's drawn in the type of life she leads, but Joel still takes a lot of time being ready to trust her with a gun. In the second game, she's driven by just how vicious the world around her is to take revenge for Joel's death, showing just how hardened she's become in the time that elapsed between both games.
1 Joel: He's Pretty Much Carefree
Joel lives pretty much the best life he really could have given the circumstances that surrounded him, that is until the past caught up with him. When he finally got a chance to settle down, he was given a nice house, went hunting for infected to keep the civilization safe, and finally gets to sing. Gone are the days of slaving away in civilization's underbelly to stay alive.