Here's a breakdown:
* The book: In L. Frank Baum's original book, "The Wonderful Wizard of Oz," Dorothy's shoes are silver, not ruby.
* The movie: MGM changed the color to ruby for the film, and the slippers became a iconic symbol of the movie.
So, Dorothy's ruby slippers were always hers. They were a part of her life in Kansas and journeyed with her to Oz.