Serena tries to come clean, but then Lily interrupts again to give her some diamond bracelet or watch or something that was her great-grandmother's, which she pulled from the safety deposit box this morning, apparently when she was over at the bank giving some random guy a bunch of money without checking up on him. Serena demurs, but Lily's feeling expansive and wants to reward Serena for... Coming back from Spain bearing opportunities for her to squander the Bass billions, I guess.
"I was going to wait until you were 21, but I've been so proud of you lately, with Brown, and graduation coming..." Serena tries to explain that she has fucked up royally, but Lily shushes her and straps the thing on her wrist, all about how Serena is becoming a wonderful woman, and now everybody will know because of this thing on her wrist. She's like, "Now that I've guilted you so bad you're trying to invent a time machine to go back and fix previous fuckups, what was on your obviously guilty conscience?"
Serena's just like, "Well, this is too extravagant, but whatever. I officially cannot tell you what's really going on, because your style of parenting is as subtle as a brickbat, and the fact that you've let up on constantly screaming BAD SERENA and THE OLD SERENA IS BACK every time I open my goddamn mouth -- at least for the ten seconds I've been standing here not getting a word in edgewise -- is about as sparkly as this bracelet, so... um, nothing. See you at brunch."
Which I love, because again you have this parallel between Old Serena and Old Georgina happening, where accusing Serena of being Bad Serena six times turns her into her, and Blair's going to be lightly flicking the foundations of Georgina's whole Perfect From Now On thing throughout the episode before just giving in and pushing the damn thing over. But then, she only does that because of the similar parallel with Real Chuck and Burlesque Chuck going wrong: If Chuck can't change, for her, then obviously nobody can change, so obviously she's meant to be with Nate and Georgina is meant to be from hell.