My cat gave birth to 5 kittens. Everything was fine and they were all feeding until today when my mom noticed one of the kittens (pretty sure it was the runt) not moving or breathing. We also noticed this and decided to keep an eye on it. This could have been because my sister would keep touching them everyday and maybe her scent got on to the kitten. I guess the mother cat noticed it was dead and started licking it to see if it was alive. I came back a little later to see that my cat ate the kitten but left it's body. Do I dispose of the dead kitten or do I leave it?
Sorry to hear the little one didn’t make it.
Right now, your cat probably doesn’t perceive it as her kitten any longer, as indicated by her starting to eat it. So for health and hygiene reasons you should remove the remains as quickly as possible.
Let her focus on and care for the other kittens. She’ll quickly forget about the fifth, especially if the other four keep her busy.