Milly's Star by Richard E. White
Approx. 5,320 words.
Published on July 2, 2012.
Milly starts having strange dreams. Always of her as a cat. Then something goes wrong and Milly has to find out whether the dreams are real or not. For the readers of the series the World of Spellmarks, this is how Milly, the master of cat magic, found her powers.