I have just learned that every major key has its own "relative" minor key. And the corresponding minor key for G major is E minor. Does that mean that "Prelude in E minor" can be written as "Prelude in G major"?
If that's the case, since a major key usually correspond to a happy tone. Shouldn't "Prelude in G major" a happy song, which, by default, makes "Prelude in E minor" a happy song?
I'm so confused.