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Tear Jerker: Eight Crazy Nights
In the film, Adam Sandler's character is an asshole to everybody, even the kindly-yet-eccentric guy who takes him in. Then it's revealed the reason for his behavior is that when he was 13, his parents were killed in a car accident on their way to his basketball game during the winter holidays. Well, we assume it would be a tearjerker if they didn't have Whitey giving the backstory.
Even worse was his reading the note in the empty mall, hearing it in his parents' voices.
Long Ago "It all seems so long ago/ Young and happy, don'cha know?"
The close of the scene describing Davey's Childhood.