All my kitties appear in the kitchen within seconds of a human being heard there. Lucy can hear the fridge being opened wherever she might be in the house- even if it's the middle and one of us is just getting a glass of water. Ozzie usually appears right away also and tries to climb right INTO the fridge. Jake follows soon after, but being older and more "dignified" he will patiently sit a distance away, wait and watch..from experience, he knows that he will usually get a treat without trying to trip me in the process!