Lorelai: It's his first night staying at your house. I want him to have all the stuff that makes him comfortable. Ooh, tennis balls! [exits]
Christopher: I actually have tennis balls.
Lorelai: [o.s.] Penn or Wilson?
Christopher: You're joking.
Lorelai: Paul Anka's must be Penn. They must be new, they must be green. Not orange and green, just green. And FYI, you might want to watch that sarcastic tone of yours because dogs are very attuned to tone. It's kind of like Chinese, in that respect, dog language. It's very tone based. And you are stressing him out right now with your tone.