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Tear Jerker: The Fresh Prince of Bel-Air
In "Papa's Got A Brand New Excuse", Will's deadbeat dad, Lou, comes back into Will's life after fourteen years, and Will tries his best to get to know him better. Even after Uncle Phil calls out Lou about not being there for him when he was a child, Will — for the first time in the show — outright defies Phil by telling him that he isn't his father. In the end, Lou's true colors show as he becomes more concerned over some new business and has to cancel a planned summer trip with Will. It's clear from their last talk together that Lou's not coming back — and Will doesn't want him to come back. Will tries to shake it off and defiantly yells about all of the things he learned to do — and hopes to accomplish — without his father around to help him. He eventually breaks down as the weight of the situation fully hits him. Will finally just looks at Uncle Phil with the saddest look on his face and says one of the shortest, yet saddest lines ever uttered: "How come he don't want me, man?". Phil then gives him a Cooldown Hug. The camera then zooms in on the present Will had bought for his father: a wood carving of a father holding a young son. Link.
Here's the rant, in all its glory:
Phil: Will, it's alright to be angry.
Will: Hey, why should I be mad? I'm sayin' at least he said "Goodbye" this time. I just wish I hadn't wasted my money buying him this stupid present! (takes the statue out of his bag)
Phil: I'm...I'm sorry. You know, if there was something...
Will: Hey, you know what? You ain't got to do nothing, Uncle Phil. It ain't like I'm still five years old, you know? Ain't like I'm gonna be sittin' up every night asking my mom "When's Daddy coming home?", you know? Who needs him? Hey, he wasn't there to teach me how to shoot my first basket, but I learned, didn't I? And I got pretty damn good at it, too!
Phil: Yeah, you did.
Will: Got through my first date without him, right? I learned how to drive, I learned how to shave, I learned how to fight without him! I had fourteen great birthdays without him! He never sent me a damn card! TO HELL WITH HIM!!!
(Phil breathes like he's about to cry)
Will: I didn't need him then and I don't need him now.
Phil: Will? Will?
Will: No, you know what, Uncle Phil? I'm gonna get through college without him, I'm gonna get a great job without him, I'm-a marry a beautiful honey and I'm havin' me a whole bunch of kids. I'll be a better father than he ever was! And I sure as Hell don't need him for that, 'CAUSE THERE AIN'T A DAMN THING HE COULD EVER TEACH ME ABOUT HOW TO LOVE MY KIDS! (long pause; Will tears up) How come he don't want me, man? (he and Phil embrace)
IN ADDITION: His tears were for the friends that he knew growing up that didn't know their fathers.
Also the part where will breaks down and his "how come he don't want me" line is unscripted and it's the actor saying it, not the character
In "Bullets Over Bel Air", Will takes a bullet for Carlton when the two are mugged while withdrawing money from an ATM machine. After seeing Will hurt so badly, Carlton's feelings of helplessness push him over the edge, and he buys a gun and even brings it with him to the hospital. Will ends up begging Carlton to get rid of it so that he doesn't intentionally or accidentally hurt someone in the same way Will was. After convincing Carlton to give up the gun, Will breaks down in tears. Link
Will couldn't convince Carlton to give up the gun gently through reason and love. Carlton only handed over the gun because Will had to use as a last resort You Owe Me.
And when Will checks if the gun was indeed loaded, he finds that, yes, Carlton actually bought a gun and loaded it with ammo with the intent to shoot someone out of self-defense, or to defend a loved one, if the need came for it. This is Carlton we're talking about.
Will confessing that the pep pills that almost killed Carlton were his. A true He Really Can Act moment by Will Smith as he slowly breaks down during his speech explaining the whole situation. Link.
After Jazz inadvertently jeopardizes Phil's chances at being a judge, Will blows up at him and tells him to leave.
Will: So, as of now, this friendship is over, you're not welcome here, so I'd like it if you just got the hell outta my crib!
Most of the series finale, for long-time viewers of the show. Even Carlton's So Bad, It's Good dancing to Tom Jones, because it was the last time we'd ever see it... and even more so when it was Will's idea and he actually joined in! In this case, though, you'll most likely be laughing your head off and tearing up at the same time.
"Home is Where the Heart Attack Is"
Will tearfully admitting that he "caused" Uncle Phil's heart attack by giving him a cheeseburger he bribed him to buy.
Carlton being afraid to see his father in such a vulnerable position, saying that he's like Superman to him. This one is softened by Mood Whiplash, though it still works pretty well in the context (one can see it as Phil not wanting to see his son so sad about his state):
"Mistaken Identity" has Carlton having his first encounter with racial discrimination when he's pulled over by a cop for driving a Mercedes in a white neighborhood. Carlton tries to deny the racism involved and justify the cop's intentions as Will tries to tell him that the justice system has flaws and that he will experience racism his whole life.
Carlton: Dad, if you were a policeman and you saw a car driving 2 miles an hour, wouldn't you stop him?
Phil: I asked myself that question the first time I was stopped. Good night, son. (leaves)
Carlton:(to himself) I would stop him.
When Hilary finally comes to terms with Trevor's death and laments that she didn't get to say goodbye to him before the bungee accident. Will comes down and tells her that it's never too late to say goodbye and that Trevor is still there in her heart. After Will leaves, Hilary stops for a moment to say to the stars "Goodbye, Trevor."