While the kittens are still young and messy I personally would avoid clumping clay litter. They ingest it not only if they eat it, but also while grooming. I really needed scoopable litter, so I used Swheat while my girls were kittens and I kept on using it because it really works. As an added bonus, it is flushable as well. Because it is only wheat, it lacks the harmful clumping agent of clay litters.