The boys are scrubbing in when Mere stomps in and orders them to apologize to each other either for their patient's sake, or for Mere, or for Lexie, who nods in agreement as she pushes an entire peanut butter cup into her mouth. Oooh, now I'm hungry again -- this show is toying with me between the vomit and then the delicious candy. Mere pleads with them to look at her sister, face breaking out, "Her ass is humongous..." Lexie adds weakly, "It's true. I had to get the scrubs with the elastic waistband." The guys don't say anything, so she announces that if they don't apologize to each other, she's not scrubbing in. Pointing out that this is supposed to be a happy time with Mark being Derek's best man only prompts Derek to retort that Richard will be his best man. Meredith looks like she's been punched, and when Mark walks into the OR she asks Lexie for a moment. Derek bitches that the best man is his choice to make, and then has the gall to ask when Mere is going to let go of her grudge against him. It's really rich, and I'm thrilled that Meredith doesn't hesitate to point this out. After reminding him how Richard had an affair with her mother and essentially helped ruin her childhood, she points out that Mark has been Derek's best friend for 20 years and he's throwing that away right now over one fight, so he can't throw stones about holding grudges. "I'll get over mine when you get over yours." Seriously, there is nothing I love more than having Derek's hypocrisy thrown in his face. Well, I might love more his not being such an ass in the first place, but this will do. After Mere leaves, Derek just looks at his friend through the window.