Kai knew Addison's history. They knew all of their secrets.
I've gotten pretty close with Addison lately. That's great! What kind of stuff do you talk about? I'd rather not say, it's pretty personal stuff. Secrets, y'know? Ah that's fair, good of you to keep it to yourself. Well I want her to trust me, which won't happen if I go telling people her secrets. I'm sure she really appreciates it!