Why wont my cleffa and dito breed?

Yup.

So i caught a clefairy, put it in the day care, it got raped by a ditto, and one of the many offspring it produced had the nature i wanted and so, like any rational wizard would do, i gave it an everstone and swapped my clafairy for my newly hatched cleffa.

And ever since the baby making rates have reduced to zero.

I had heard that you couldn't put a parent and child together and get an egg, but i did that with my zouras and got numerous eggs.

Still, i caught a new ditto, and swapped it for my old one however, still no babies.

The man at the daycare says they like to play with other pokemon more than each other which according to my memory, is a 20% chance for an egg. But i have been running around and ev training and still nothing.

ANSWER MY QUESTION.

Clefa is part of a group of pokemon called baby pokemon. Any pokemon in this group will not produce eggs and you'll have to evolve it before it can have eggs.

You can find a full list of baby pokemon on this page
http://www.serebii.net/games/breed.shtml