An October 2012 email chain ( http://archive.is/iPTNh) ) initiated by Hillary aide Philippe Reines, later Deputy Assistant Secretary of State, contains a transcript of an interview Hillary did with Monica Langley of the Wall Street Journal. This was the resulting article: http://archive.is/1nGVE .

In the transcript, Monica mentions that sometime around the opening of the U.N. General Assembly (which began in New York on Sept. 18, 2012), Hillary attended a pizza party with Bill and Chelsea. Monica recounts how Hillary's childhood friend, Betsy Ebeling, said that she likes Hillary's longer hair. It's unclear what this anecdote has to do with the pizza party, but Hillary and her staff appear to be taken off guard by the mention of "pizza party," and Hillary steers the conversation back towards UNGA.

[Editing to add: It sounds like Betsy was at the pizza party, and complimented Hillary's hair at the event, and then recounted the incident to Monica.]

Here's the relevant portion of the transcript:

From: Reines, Philippe I reinesp@state.gov Sent: Thursday, October 11, 2012 3:06 PM To: Nides, Thomas R; H Cc: Adler, Caroline E

QUESTION: Okay. Now then you go to New York for UNGA. But I talked to Betsy, your friend from Park Ridge.

SECRETARY CLINTON: Right, right.

QUESTION: Okay. So she brought this up on her own about your hair.

SECRETARY CLINTON: (Laughter.)

QUESTION: She said –

STAFF: I'm amazed you got — what –

QUESTION: (Laughter.) The pizza party –

SECRETARY CLINTON: Oh, right.

QUESTION: At the pizza party –

SECRETARY CLINTON: Right, right.

QUESTION: -- she said to you she likes your hair long, and she said it suits where you are in your life right now. Do you remember her saying this to you?

SECRETARY CLINTON: Honestly, I don't, but –

QUESTION: Okay. I don't even bring this up.

UNCLASSIFIED U.S. Department of State Case No. F-2014-20439 Doc No. C05792589 Date: 11/30/2015

SECRETARY CLINTON: No, I don't. I mean –

QUESTION: You hear about this all the –

STAFF: I can't believe you're using poor Betsy as a device.

QUESTION: I know. This is great.

SECRETARY CLINTON: I would be happy to talk to you sometime about all of— all that, all that stuff.

QUESTION: Yeah, yeah, but not that. But she said that. Okay. All right.

SECRETARY CLINTON: (Laughter.)

QUESTION: So anyway, so you have the pizza party, then — and your husband and your daughter are there.

SECRETARY CLINTON: Right.

QUESTION: At least that was a nice break.

SECRETARY CLINTON: Right, right.

QUESTION: Okay. Then you go into full-scale work.

SECRETARY CLINTON: UNGA, UNGA, UNGA.

QUESTION: Okay. But you first appeared at the Clinton Global Initiative, which was a key –

SECRETARY CLINTON: Well, no. I started working on Sunday.

QUESTION: Oh, okay, okay.

SECRETARY CLINTON: I was at the Clinton Global Initiative Monday morning, but I started having what we call bilats on Sunday.

QUESTION: Okay. Yeah. And I wrote down you did — it looks like you had 29 bilats, you had 54 meetings or events that week. And I don't know if you noticed, but I was running in as a little pool reporter just to see any glimpse of you.

SECRETARY CLINTON: (Laughter.)