A girl sees a boy with a box of kittens. She goes over, looks at them and says "Oh what cute kittens", the boy replies "I know, and they are Christian kittens".
About a week later she sees the boy again with the same box of kittens. once again she walks over and says "My, aren't they just adorable!" the boy replies "Yes, and these are atheist kittens"
She looks at the boy and says "Hang on, you said they were Christian kittens before?"
The boy looks at her and says " Yeah they were, but now they have their eyes open"