Very sorry to hear about your cat.
Not knowing any specifics about the cat other that it was a she, have you tried to search the AHS database?
http://www.daylilies.org/Dayli...
I typed in both "cat" and "kitty" and looked for them at the beginning and end of the name. It came up with several, but Precious Kitty and Cat Dancer looked like the best ones. But you may see something that fits. For instance, there are daylilies named Calico Cat, Black Cat, and Cool Cat.