My tendency to neurotically check if my cats are alive when they're sleeping has inadvertently trained one of them, Tony, to be a very deep sleeper, a fact which wound up alarming all of us when she zonked out on a footstool as we were watching sports*.

(*D&D)

Because the deeper she sleeps, the more anxious I get to provoke a response from her, which has created a sort of arms race style escalation.

With Tommy, it doesn't matter if she's asleep... if I call her name, she's by my side in twenty seconds.

With Tony... you can pet her, poke her, jiggle her. Pick her up. If she's out, she's out.