I have often said Trixie thinks she is a dog and Callie thinks she is a cat. It was merely an observation based on their attitides and actions, not a desire to have Callie become a cat and Trixie turn into a dog.

It would be rather comical though to have them swap.... another "Freaky Friday" scenario! Callie would be thrilled to be able to jump up and eat the cat food that she cant reach. Trixie would finally be welcome outside. Then they would realize they liked their real lives and wish upon a star that they return to their own fur.