I have been fostering a litter of abandoned kittens for about a few months. They have all found homes but one.

One in particular, has been returned 4 times because people don't want to deal with unpleasant sight or "kisses" she leaves behind when she sits.

This kitten has been to a vet; she eats a vet-approved diet, and she is not sick in any way.

In a perfect world, people would accommodate this kitten's shortcomings by wiping her rear end. This world isn't perfect or kind to animals that don't adhere to standard expectations. Just about everyone expects a cat to groom themselves. I understand Reddit likes to leave unhelpfully sarcastic comments, the older this kitten grows, the less likely it will be adopted. I'm a foster under a program; if she's returned again, she's turned over to a regular animal shelter to make room for the upcoming litter.

This question is serious.

How can I teach the kitten to properly groom herself?