In the actual fairy tale, the little mermaid is first allowed to visit the surface when she turns 15 – and there's some very particular decor she has to wear when she does:
Oh, and about that ending. Basically what happens in the book is the prince marries someone else and the little mermaid turns into foam and then some kind of air-being:
Possibly the worst consolation prize in history.
In the actual fairy tale, Snow White is often referred to as a "child" for a lot of the story. In fact, she isn't even a teenager when the Queen first asks her iconic question:
Kids, amirite?
Speaking of the Evil Queen, in the Disney film she of course meets her demise by falling off a cliff. However, in the actual fairy tale the Queen shows up to Snow White's wedding before meeting a slightly more intense end:
Hot. Literally.
In the actual fairy tale, Cinderella has not one, but three different gowns (which she receives from a tree and some birds, not a "fairy god mother.") Also, it turns out those famous slippers aren't even made of glass:
"I love gooooooold."
In the actual fairy tale the stepsisters attempt to make Cinderella's slipper fit by cutting off a toe and a heel (respectively). And on top of that, they make the mistake of attending her wedding:
♫ Blinded by the light, er, pigeons? ♫
In the actual fairy tale Maleficent is just another one of the fairies (which, BTW there are 13 of). Also, they're not even fairies, but "wise women" – and thanks to the King's weird policies Maleficent gets totally screwed over:
Still, she can obviously rock a cloak and dress in any color.
In the actual fairy taleFrozen is super loosely based on, there is no Elsa. However, there is a little boy named Kay and just like Elsa he has a sister (OK technically, a friend, but practically a sister) who goes on a crazy journey to find him: