A 20-day-old kitten can defecate on its own, which is a normal physiological behavior for kittens. However, because kittens are small, they may not use a litter box or may defecate anywhere. Therefore, owners need to teach them to use a litter box and observe their defecation behavior.

If a kitten is unable to defecate on its own, the owner can gently stimulate the kitten's anus with a cotton swab to help it pass stool. In addition, the owner needs to pay attention to the kitten's diet; dehydration or overly thick food can also cause difficulty in defecation.