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Tearjerker: The Sixth Sense
"You were never second."
"Do I make...her proud?"
The video Cole gives to Kyra's father at her wake. It's of Kyra putting on a puppet show by herself in her room. And then, because she didn't turn the camera off, it records her mom coming in with her lunch... and then pouring two cups of floor cleaner into her food, stirring it around, and telling Kyra she expects her to eat everything. Just, her father's realization of seeing one of his daughter's last moments leading directly to his wife deliberately poisoning her.
"You were keeping her sick."
In a deleted scene, Cole using his toy soldiers to recreate what are clearly real stories of the ghosts he's seen, including the families they left behind. Shyamalan even says he hated to cut the scene because of how effective Osment was in it.