hey hi hello! i'm watching the film again but is has been a while since i've posted any headcanons so per the request of @leslie114 here's some more!
this is how i see adult sam. here's my shitty ass photoshop edit. i made him emo again cos i CAN and I WILL because ONCE AGAIN, i hate the "look lighter, feel lighter" trope so much. YOU CAN BE EMO AND BE HAPPY. YOU CAN BE ANY ALTERNATIVE STYLE AND BE HAPPY RAHHHHHHHHHH.
sam becomes an architect like george, but also like his grandfather (as mentioned by kurt in a deleted scene with george), he helps in building the houses as well.
SAM IS BI. yes, he said with his whole heart "im not gay" but i did that shit too in high school. suprise sam. you're a little fruity. though, it being in 2001, he def has conflicted feelings about it especially with how others react to the possibility of him just being "gay" because of him putting on eyeliner. plus, the whole scene with being pimped out ... yeah, that didn't help him.
he was using various substances for four years, his withdrawals are going to suck. i wish it was shown in the movie bc even with me using weed for two years, that shit was hard to cut off. nausea, sleepless nights, appetite shifts, irritibility, the depressive episodes. fuck, that cranked up to 740327407204% while he's 16? plus his father dying? it would honestly be a surprise if he stayed sober.
thus, i don't believe he does. one, it sucks. you want it to stop so you fall back into bad habits. two, he's 16. he's going to make some dumb decisions and judgments because he's still growing and learning. i've done some stupid shit when i was 16 (literally the worst year of my life honestly), but hey. made it out to the other side.
manson switches out for nine inch nails. fuck manson. get that abuser shit off your walls.
george 10000% tells sam about alyssa kissing him. not in the typical way you'd think, but probably an offhanded mention that makes sam double take like HEY WHAT and this takes place sometime during his hospital visits.
his relationships with ryan and adam do overall improve, but ryan def a lil homophobic but with separation from peter, i think that it would be better. like sam, ryan notices the shift in his parents, and as peter retracts more and more, he favors robin.
again, 1000% believe that peter and robin divorce.
sam also does take long drives sometimes when he feels like he needs to clear his head.
he's really happy when he sees his parents get back together. i imagine it's a rollercoaster of emotions for a kid of divorced parents to go through. parent trap all over again.
he likes to sketch sometimes. if he's with someone, he'll sketch them a lot, and have a specific color attributed to them. he's quite talented with it.
after the peter and robin separation, sam can relate to it, so when ryan or adam ask him to do something/go somewhere, he usually agrees. he knows it'll help distract them for a moment.
he's slow to find his Person, but once he does, he's got walls up. once that person knocks them down, he falls hard for them.
he rarely drinks. he knows what he's like with smoking, and doesn't want to make things worse. he'll do it socially. plus, being drunk is a worse sensory feeling for him. he prefers to be high. occasionally, he will be crossfaded, but more so on the smoking side with max 3 drinks.
he often visits george's grave as he goes through university for architecture, sometimes even working on physical models beside the plot while he talks about what's going on.
george is ofc always there, even if sam can't see him. he's very proud of his son.