Well of course, silly. She's a *cat*.

Penwiper strolls through the living room into the dining room, where I am sitting.

Me:  Good morning, sweetheart.
The Rocket Scientist, from the kitchen: I assume you were talking to the cat, not me.
Me: That's right -- how did you know?
RS:  You never call me "sweetheart."
Me: True.
RS: Hey, I know where I fit in the hierarchy around here.*

*I asked him if he wanted me to call him "sweetheart," and he said no, as long as I did not start calling the cat "dear."