I did that once w/my meezer Coco Puff except he didn't yell. He just sat there like a "kittiot" so it was quite a while before I realized he was missing. I began to panic when I couldn't find him and I opened the door because I thought he couldn't possibly have gotten out and there he was sitting there patiently. I guess he was watching the world go by through the storm door glass. He was fine and I'm glad Cassy is, too.