The next morning, Mary comes below stairs and after everyone gets to their feet, she asks if any of them might have taken a letter from Lavinia on the day she died? Unfortunately, no one pipes up and Carson thinks that, given the events of the day, if there had been a letter it would have been reported to him or Mrs. Hughes. Mary tries to hide her disappointment and she quickly withdraws, but Daisy comes in with another couple plates of food at that exact moment, and when she hears what Mary was there for, she says that she posted Lavinia's letter. Mary apparently was within earshot for this -- maybe she was taking a moment to recover -- and, as she walks back in, Daisy explains that she was in tending Lavinia's fire when Lavinia started chatting her up -- "she was ever so nice" -- and asked her to post the letter, so she put it in the box in the hall. Mrs. Hughes starts to scold her, but Mary cuts that off right quick and says she's so grateful to Daisy and Daisy at least has the good sense not to try to parlay that gratitude into a new kitchen maid.
Upstairs, Lord Grantham seems finally to have made peace with what's happening, and he does point out that of all three of his girls' husbands, Sir Anthony is the most traditional choice -- I'M SAYING -- but the Dowager Countess, with real emotion that at least makes me think she cares about Edith, says that Edith will be starting married life "as an old man's drudge." Of course, you can't expect any such outpouring to stand for long, so when Lord Grantham asks why she's on about this now, she replies, "Because I want the pleasure of saying 'I told you so.'" Hee.
Mrs. Hughes and Mrs. Patmore are dressed to go to the church when Carson comes in and is like, are you sure about this wedding/maybe you should lie down/how about I carry you about in my arms for the rest of the day, and Mrs. Hughes -- getting a bit exasperated -- says it would be nice for people to wait until she knows she's ill before "boxing me up." Carson's like, illness, what illness/who said illness/I don't know anything about any illness, and he's about as convincing as Manuel on Fawlty Towers saying "I know naathing." When he's gone, Mrs. Hughes tells Mrs. Patmore that the doctor will have the results back the next day, and she's to call in the afternoon...
...while upstairs, Anna finishes with Mary and heads off to attend to Edith, leaving Mary alone to tell Matthew what she learned. Matthew looks like he can't take it in and he sits to process it, but for once, his facial expression doesn't look tortured and I don't know if Mary sees it too, but either way she goes for it: "If you try to find one more excuse not to accept the money, I'll have to beat you about the head." I'm surprised it took you this long to come up with that solution, Mary. I was there somewhere in the middle of last episode. Matthew laughs, and it's not just in humor but also in relief that he can let go of at least part of his crushing guilt, but he does tell Mary he has one condition -- that they wait until after the wedding to tell Lord Grantham. "Let's not steal Edith's thunder." Make your own joke here while I go see my chiropractor.