Dear girl cat,
I'm really sorry that the dry food bowl went empty over the night. But did you really have to let me know about it at 4:18 am? Couldn't it have waited until I got up at 5?

Dear boy cat,
Congratulations! After a decade of hard work, you've finally got me trained. Proof: when I was washing dishes last night and you came up and yowled at me, I stopped what I was doing and gave you a kitty treat. Didn't even think about it, just responded to your stimulus in the way you desired. Good job!