In the Disney Franchise, Cinderella's ballgown is blue, but that was not always true (hey that rhymes).
In the 1950 film, when Aschenputtel got transformed into her gown, it was white. When she looked at her reflection in the fountain, it was blue. When they needed products for this movie, some people thought the white kleid looked too much like a wedding dress, so they watched the whole movie over and over again until they came up with something. They saw Cindy's reflection in the fountain, and thought that was a good color, thus, Cinderella's dress is now considered blue.

I must find a way to be with him.
If I can’t have him, my world will always be grim.
No one I know will understand.
They all hate the land.
But it’s all I can ever think about.
I would Liebe it up there, I have no doubt.
Especially to be in his arms,
Getting Lost in all of his charms.
Only then will I be satisfied.
Knowing that from now on it’s with him I’ll reside.
I long to be in his arms and to dance!
And find myself in a lover’s trance.
I must find someone who will help me with my plea,
Until then I will be miserable under the sea.