Meredith dismisses a grateful April, and then finally tells Lexie about the miscarriage and how April was there when it happened and that's why she knows. Lexie drops her head, already sorry, but Mere goes on that she knew Mark slept with Amy but that she also never has any idea of what is going on between him and Lexie, so she didn't think Lexie cared, and then finally tells her sister that she sat by her bedside for 36 hours while she slept in the psych ward, so she is very much not alone. Lexie starts to cry as Mere tells her with a smile that she's not crazy, she's great, and I sincerely hope that it sticks because I like Lexie but her complex about having been committed was getting a little out of control.
"We stop competing." Callie and Mark are on their way out when Arizona decides to be an adult, and calls after them that the plans have changed, and Mark is taking her out instead. Mark asks if this is to make up for the fact that she doesn't like him and Arizona figures Callie told him, but she didn't, Mark figured it out all on his lonesome because he has half a brain and Arizona was anything but subtle about her seething distaste for him. Why does everyone on this show think they're being so sneaky when they're being loud and obvious about every emotion that they have, every second that they have one? Mark agrees but tells Arizona she's buying, and a relieved Callie kisses her and thanks her. As they walk off, Mark asks if she still wants Italian, and she tells him to move his eyes back to her face. Wait, wasn't this all about sushi? Don't waste a good sushi reservation, people!
"We learn from our mistakes." The lodgers are once again having group bathroom time but Lexie kicks out the boys so that she can have some alone time with a petrified April. She immediately tries to offer Lexie the room but Lexie cuts her off and points out that she admitted she wanted to drive a car over her earlier, so she can totally have the room. But she does put down her foot about the chore wheel, saying if one goes up, she'll kill her. April laughs, but her eyes show she knows Lexie's not entirely joking.
"We face our greatest fears." Meredith is reading in bed when Derek gets home, and they have some kissy time but he realizes something is up, and she finally admits that she's getting tested for the Alzheimer's gene. Without any hesitation, he tells her, "Don't." She thinks they should know, and points out that if it turns out she can have a baby she could then get Alzheimer's and wind up not recognizing it or worse, she'd pass it along to them, and Derek would wind up having to care for both an invalid wife and child. But Derek is dead serious that he doesn't care and he doesn't want to know. When she admits the lab already has her blood he tells her what the plan should be -- they have lots of sex, they either get pregnant or they don't, she'll either get Alzheimer's or not, but they will just live their lives and enjoy themselves. "Whatever happens, happens." She looks quite worried at this idea, but finally smiles and agrees, and they resume kissy time. Since she pointed out that her blood is already at the lab, I totally wonder if she's going to succumb to curiosity and find out the results anyway, but that will be a story for another episode if it comes to pass. VO: "For better or worse, we find ways to become more than our biology.