Casper's purr is LOUD, and I mean loud! Aunt Sandy once said that while Casper is purring, our walls are shaking! He purrs when he's in our lap, or when we pet him.

Kitty's purr on the other hand is quiet, can hardly hear it (yeah, we're half deaf after Casper's purr ). And she also purrs when she's in our lap, and when we pet her. Also, if the food we serve is especially yummie, they purr.