So Harry was meant to marry somebody else? Who was it? Was it Ron?
If you want to know the answer to this and 6 other very important questions, watch the video!
The Philosopher's Stone, The Chamber of Secrets, The Toilet of Uncertainty...
Okay, so we made that last one up, but Harry Potter books are ridiculously popular around the world.
Because J.K. Rowling wrote the books, she decided to give herself the same birthday as a familiar Hogwarts student.
Was it Ron? Or how about Hermione? Surely it wasn't, you know, He Who Must Not Be Named?
Loads of people wanted to star in the Harry Potter films but J.K. Rowling didn't want to let just anybody appear.
And for all the stars that DID make the grade, such as former Dr Who David Tennant or Radiohead star Johnny Greenwood, there were plenty of disappointed celebs who never even made it as far as the Sorting Hat.
So everyone ended up in love at the end of the movies. Pretty gross, right?
But even though it was meant to be happy ever after for Harry, J.K. Rowling revealed she wasn't satisfied with the ending she wrote.
So who should Harry have been with instead?
There's lots of weird and wonderful language in Harry Potter, with Squibs, Snitches and Butterbeer just some of the examples.
And even though some of them might sound made up, in fact J.K. Rowling found a lot of these words from reading books about ancient ways of speaking.
With all the props and crazy costumes on set, it's no surprise that sometimes things got out of control.
Tom Felton, who plays Draco Malfoy, had to have his pockets sewn up to stop him sneaking food into the Great Hall.
And as for poor Hagrid's beard....
The Harry Potter movies are full of fantastic beasts and we all know where to find them. Well, sometimes we do.
Especially when the fantastic beasts in question are owls. Because everybody knows where owls live, right?