And one fan who's been re-watching the iconic movie has spotted a tiny detail in the film that we've never noticed before - and it explains everything.
To recap in case you've not watched it recently, Home Alone focuses on Kevin McCallister, whose family accidentally leave him behind when they jet off to Paris for Christmas.
When Kevin wakes up alone after his family have rushed off to the airport, he thinks it's his fault - after all, just hours before he had wished his entire family would disappear in the heat of an argument.
Of course, Kevin's mum and dad soon realise they've forgotten their son - but only while on the plane to Paris - and the next few days sees the family doing everything they can to get home.
Meanwhile, Kevin is alone, and having to protect his home from two burglars who have been plotting to break in while the family are away.
But after watching the movie zillions of times, many fans have often wondered why Kevin's family didn't realise he wasn't with them at the airport?
Well, one fan has found the answer - and our minds are blown. As we know, one of the reasons Kevin wished his family would disappear was because he got into a fight with his brother, Buzz.
During the argument, drinks are spilled and the family's plane tickets end up getting soaked.
Writing on Twitter, the fan explained: "I have seen Home Alone probably one billion times, but was today years old when I realised they threw out Kevin's plane ticket during the pizza debacle and that's why no one figured out he was gone earlier at, like, the airport."
I have seen Home Alone probably 1 billion times, but was today years old when I realized they threw out Kevin's plane ticket during the pizza debacle and that's why no one figured out he was gone earlier at, like, the airport pic.twitter.com/ONVKPzMtxJ
- Nora Brown (@NoraAndFauna) December 7, 2020
And other fans are only recently noticing it too, with another adding: "Watching Home Alone for the 50th time and I've never noticed that in the starting scene when there is a fight in the kitchen, Kevin's ticket is put in the bin. Who knew?"
"I have watched home alone at least 3 times a year for the last 30 years and have only just realised that they throw Kevin's plane ticket in the bin at the start!!!" Added another.
We can't believe we never clocked this before?
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