As they walk down the hall, Izzie thanks Mark for picking her, because even the chance to observe the surgery will be great. He tells her, "I thought you might be fun to look at while I worked." You know, I thought the same thing about McSteamy when he first joined the show, but it really hasn't worked out that way. She asks him a medical question, and he tells her to fetch him a blueberry scone and a bone-dry cappuccino. He tries to hand her some money, but she doesn't take it. Izzie: "There's a cafeteria on the second floor and a coffee cart in the lobby." And this is the Izzie I once loved. Mark calls her "feisty" and again asks for the cappuccino. Izzie: "You can kick me back to Bailey if you want. I don't do coffee." He gives her a look and walks away, and she runs after him asking medical questions about the surgery.
The Chief and Derek are in a dark room surrounded by x-rays of Jacob and Peter. The Chief is gushing, all Donald Trump about how this surgery will be yoooge for the hospital. And then Derek pulls a Melania, by which I mean he tells the Chief that he'd rather not. Do the surgery, that is. Derek is doubting his abilities, don't you know, and he thinks the risk that the twins will end up paralyzed or dead as a result of the surgery is too high. The Chief tells him that the surgery is going forward, so he should just suck it up. (That Donald/Melania metaphor just keeps working, doesn't it?)
In the Corridor of Discomfort, Susan is telling Meredith and Addison that Thatcher (Meredith's father) isn't there because he's off visiting their other daughter at med school. (Which he thought he could do because the baby's not due for a while yet.) Meredith asks Addison if she needs anything else, and Addison asks her to get Bailey to assign an intern to the case. Meredith looks around and then tells Addison that she'll do it. After a little back and forth, Addison agrees. I don't know -- don't you think it might get kind of awkward, operating on your own half-sister? Too bad the hospital doesn't have a rule against interns working on their family members. Susan thanks Meredith for "being there," and Meredith tells her, "It's my job to be here." And then, to avoid any unintentional outing, Mere asks if Molly knows that Meredith is her sister. It turns out that she doesn't, because Thatcher decided to keep Meredith's identity a secret. Addison tells Susan to get some scrubs, because the surgery is ready to start and she's going to be there as Molly's coach. Susan is tense about becoming a grandmother. Addison leads her down the hall with a "here we go," which Susan and Meredith repeat in decreasing levels of enthusiasm as they follow after her.