After the success of Nintendogs, Nintendo considered many ideas for a followup, including horses and dolphins. Many people asked for cats, and they went as far as creating a test build where they replaced the dog models with cat models, though they did not change the behavior, so the cats did things like wag their tails.

However, it was not until Shigeru Miyamoto got a cat himself, and the way his dog and cat got along reminded him of the 1963 Disney film The Incredible Journey, that he felt he inspired to make a sequel with cats: