Everyone is familiar with the holiday classic Home Alone. But no matter how many times you watched it as a kid, there's probably one thing you missed. But once you know what it is, you'll wonder how you missed it this entire time! 

In Home Alone, Kevin (played by Macaulay Culkin) finds himself constantly annoyed with his family. The night before their annual Christmas trip, Kevin wishes his family would disappear. 

Kevin then wakes up to find out his wish came true. His family disappeared, just like he wanted. Hijinx ensue.  

But there's one gaping plot hole that you've never questioned, no matter how many times you've seen this movie. How did his family overlook the fact that Kevin was gone until they were already on the plane? Surely his parents aren't that bad at parenting. 

Every family member had a plane ticket. When they were boarding the plane, they would have noticed that they had a ticket for Kevin, but no Kevin. They would have turned around and gone home, thus ruining the whole point of the movie. 

Well, there's a really simple explanation for this. The night before the trip, the McCallister family orders pizza. Presumably because nobody wants to do dishes the night before a trip. This logic checks out. 

Kevin spills milk. His milk lands all over the passports and airplane tickets. While this seems like an innocuous moment, it's actually the moment that the whole film hinges upon. So pay close attention! You might be quizzed on this later! 

Kevin's father cleans up the spilled milk. But when he does, he accidentally throws Kevin's boarding pass into the trash. If you look closely, you can even see it during the movie! It's got his name on it and everything. 

The next morning, they get in a van to go to the airport. Kevin's sister Heather counts to make sure that everyone's there. However, a neighbor is standing in with the McCallisters which makes Heather miscount. Which makes everyone think that Kevin is there. 

Of course, the night before, a windstorm blew out the power, resetting their alarm clocks. This made everyone oversleep. When they woke up in the morning, they were in a rush to get to the airport, which means they were more likely to overlook missing Kevin. 

There's another reason why nobody notices that Kevin is gone when the family boards the plane. The flight attendant doesn't call the passengers by name. The attendant lumps all of the McCallisters into a group, then counts their tickets. 

Kevin's ticket was conveniently in the trash. Had Kevin's ticket not been thrown away, they would have noticed that they were short one person. And, they would have gone home to get Kevin. We hope, anyways. 

But there's also another unsolved question in Home Alone. When Kevin found himself, as the title suggests, home alone, why didn't he call the cops? This eight-year-old kid is just hanging out by himself and doesn't think to get the authorities involved. 

His house is even looted by criminals, but Kevin still doesn't think to call the cops. He just decided to take care of the problem all by himself. Why? Well, it's because Kevin thinks he's a criminal himself. 

Earlier, Kevin steals a toothbrush from the store. It's an accident, but it's still enough to wrack his eight-year-old head with guilt. He even whispers to himself, "I'm a criminal." 

Because of this, Kevin is forced to take on the Wet Bandit Gang all by himself. He booby traps the house so that when they try to rob it, they end up getting a tarantula in the face instead. Why would Kevin get the authorities involved when he's guilty of his own crime? 

So as it turns out, what seems like a major plot hole isn't really a plot hole at all. You just weren't looking close enough! Those clever screenwriters thought of everything, huh? 

So go ahead, watch Home Alone again, you filthy animals! You'll enjoy it on so many more levels now. You're welcome!