As weird and sad as it is, Alicia's discretion is really a treat here. She knows what he's asking and she knows that he is okay with his dad, but she also knows what Zach's wrestling with, and how to help without actually touching it or digging any deeper than it takes to say the exact minimum to be both honest and kind. Good thing she's ramping up her subtlety, too, because guess who is at the door and not in the mood to be subtle at all?
Diane: "Hey Alicia, sorry I'm at your house I've never been to, but they told me Peter was home and I was like, Well, I guess I'll go over there to his home. Where he lives. Your home. Do you know Peter Florrick? State's Attorney? Humiliating us?"
Alicia: "He's not here at the moment, but goodbye okay?"
Diane: "You know that normally I would never even think of forcing entry into your home, but... Here I come."
Diane explains about the auction and the audit, and Grace appears just in time to hear Alicia not say, "Well, that's a bummer because you fuckers are dirty," and Diane's like, "Cute kid, but anyway, I asked Peter if we could use an independent firm but he's insisting on a departmental audit."
Diane, verbatim: "That would open up our books in an alarming way."
Alicia's face: "Um, you saying that is, in itself, kind of alarming."
Diane: "Also, the two other ones aren't being asked to do the audit. Just us. Just little old Lemond Bishop-representing, his-wife-employing, Eli Gold-housing Lockhart, Gardner."
Alicia: "Yeah, that's like ... so weird."
Diane: "Lady, give me something. Why is your husband dicking us?"
Alicia, verbatim: "Diane. I've worked hard to keep my home life separate from my work life."
Translation: "Get the fuck on up out my house."
Diane, verbatim: "I know, and I respect that. But I need to know if Peter is doing the same."
Translation: "You knew when you said that it was going to eventually be a lie. The second you put up the art in your new office you knew this shit was coming. If your connections are no longer helpful to the firm, that's one thing, but if you're making us a target I will take you down."