A kitten with a bulging belly that does not poop may mean that the kitten is not able to defecate yet and needs to be guided by its owner to defecate. Kittens need the mother cat to lick their buttocks to stimulate defecation. The owner can wipe the kitten's buttocks with a warm towel to stimulate the kitten to defecate. If the kitten still does not defecate, it is best to take the cat to the pet hospital.