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Tearjerker: Harry Potter And The Goblet Of Fire
From the Book:
Harry mentions that it's Voldemort and his followers' fault for destroying families: mentally shattered Neville's parents, implied to have hurt a member of the Abotts, killed Moaning Myrtle, ruined the Crouch family, killed most of the Tonks family, forced the Malfoy family to be separated, and killed Harry's parents, godparent, and James's friends.
Harry thinking about his parents never hugging him like that when Molly hugged him. Not to mention that all the while, Harry was fighting back tears over Cedric's death.
Harry: I told him to take the cup with me.
Cedric's father, who acted like a pompous Jerkass towards Harry, didn't take the Triwizard winnings and also let him know that he doesn't blame him for Cedric's death.
Dumbledore's speech at the end eulogizing Cedric. Cho crying silently, Harry sitting there in shock.
When dead Cedric asks Harry to take his body back to his parents.
This piece is sad:
"And now another head was emerging from the tip of Voldemort's wand... and Harry knew when he saw it who it would be... knew, because the woman was the one he'd thought of more than any other tonight..."
Cedric's death is so tragic because not only was he the epitome of a Nice Guy, but because he died for being in the wrong place at the wrong time.
"Kill the spare!"
From the Film:
The moment when Harry returns from Voldemort's revival party with Cedric's body.
What really makes this scene work isn't the contrast which was still good, or even the father shouting, but rather Fleur's horrified reaction.
I will watch the whole movie just for this scene, it's that good.
That was the first time this troper shed a tear in a Harry Potter film. It was the ugly cry.
For this troper, the worst part is Harry sobbing that he couldn't leave Cedric's body behind and Dumbledore gently telling him "He's home. He's home. You both are." Utterly heartbreaking while also showing just how much Dumbledore cares about Harry.