How small are we talking?
How big are we talking?
We don't keep them in the hospital, but we sure do keep doctors around dangerously small and giant sizes. ...health problems, and all that.
But yeah, you're right. The cat doesn't seem too small. I've seen smaller. Like Rave said, you can get him checked if you're worried.
*abu moment* The best medicine for your loved ones is a smile on your face! Let them know everything's fine, and it should keep their spirits up! It works on cats too!