Who is The Kitten, from "A Dream of a Thousand Cats" from The Sandman and what is their importance?

The story "A Dream of a Thousand Cats" begins and ends with a small kitten who sneaks out of the house at night to listen to the Siamese cat speak. The kitten believes the Siamese, and at the end of the story she dreams the Siamese cat's dream of cat dominance.