In the van with the polka band, Kevin's mom worries that she's a bad parent. Gus comforts her by talking about what terrible dads all the band members are.
Gus tells her that he accidentally left one of his kids at a funeral parlor all day. By the time Gus and his wife found him, the boy was traumatized—but started talking again after six or seven weeks.
This doesn't cheer Kate up.
We offer another slow-clap for Gus' ineffective story.
The next morning—Christmas—Kevin wakes up and rushes downstairs, hoping Santa gave him his family back. But no one's there.
The polka band drops Kevin's mom off, and she heads inside, calling out to Kevin. He comes downstairs and they happily re-unite, hugging. Kate says she sorry for leaving him home alone.
She says the rest of the family couldn't make it back in time—but then they all walk through the door. Turns out, they took the flight the mom didn't want to wait for.
When the mother worries that they don't have any milk or anything, Kevin tells them he went shopping the day before. Everyone is surprised.
Otherwise, Kevin tells them he just hung around.
Kevin's dad finds Harry's gold tooth lying on the floor, and is mystified as to what it is or where it came from.
He doesn't know it's a token of his son's own brutality.
Kevin looks out the window and sees Marley hugging his granddaughter and celebrating Christmas with his formerly estranged son's family—they've reconciled. Kevin waves to him from the window and he waves back.
Our hearts are warmed.
Suddenly, Buzz shouts from upstairs, asking Kevin what he did to his room. Startled, Kevin runs away from the window.
But we know that Buzz is no match for Kevin, Destroyer of Worlds.