The day after Thanksgiving, the entire Spier family sits outside playing a game. Alice is home from college, and Simon finally realizes how weird it's been without her. Simon's phone buzzes with a text from Martin, immediately tanking Simon's mood. Martin mentions that his brother is home, and Simon can't tell if it's a joke or a threat. Finally, Alice offers to get her package of cookies out of her suitcase, and Simon feels as though the evening will be okay. The family moves to the living room, where Nora gets peanut butter so they can have "Nick Eisners"—cookies with peanut butter on top, which is what Nick thought peanut butter cookies were when he was a kid.
The "Nick Eisners" illustrate how, even as all the characters grow up and move towards adulthood, there are still parts of their past and their childhoods that will remain integral parts of their identity and family traditions.
Alice asks how Nick is doing and is happy to hear he still loves his guitar. She's quiet for a minute and then asks if they remember his bar mitzvah. Nora giggles, and Simon throws a pillow at Alice. At Nick's bar mitzvah, Simon had danced embarrassingly to "Boom Boom Pow," and he hasn't yet lived it down. Alice wishes she could go back and just stop herself from doing weird things in middle school, and Nora wishes she could do the same. Simon finds this perplexing, as Nora was normal and popular in middle school.
When Simon is perplexed about Nora's reaction, it makes it clear to him that Nora has an inner life that clearly diverges from what he and others perceive her. This brings to light the fact that while Simon certainly assumes things about his sister's identity, those assumptions aren't necessarily true and don't entirely describe her lived experience.
In school on Monday, Mr. Wise hands back quizzes on Thoreau. Simon is amazed when he discovers he got 100% until he realizes that Mr. Wise gave him Bram's quiz. Bram shyly accepts his quiz from Simon, and Simon tells the reader he thinks that Bram is probably funny in his own head.
When Simon makes this observation about Bram, it indicates that Simon is beginning to think more critically about those around him and is becoming more curious about those people as he develops his capacity for empathy.
At rehearsal that afternoon, Abby is frantically and silently running lines when Simon interrupts her. He assures her that she'll be fine to have them memorized by the end of Christmas break, but she insists that he doesn't have any lines so it's easy for him to say. She immediately deems her reply bitchy, and Simon plays along. However, Martin hears Simon jokingly call Abby a "stealth bitch" and takes major offense. Simon thinks it's ridiculous that Martin is blackmailing him and trying to take the moral high ground, but he feels awful for calling Abby a bitch anyway. He also knows that Alice would be disappointed in him. He apologizes and heads onstage.
Simon's mention of Alice shows just how much he idolizes his older sister. In her absence, Simon must learn to monitor his own language now that she can't do it, which is partially to blame for his sense of guilt here. This illustrates another way that the entirety of the Spier family is growing and changing as the Spier children get older.
Simon looks around at the drama club and notices one girl crying over something someone wrote on the Tumblr. He thinks that he was destined to be nosy, as Simon means "the one who hears," and Spier means "the one who watches." Simon smiles at Cal and feels his day might be getting better—until he notices that a girl's ankle is crossed over Cal's. It's raining when Simon leaves rehearsal, which makes him feel even worse, and he feels like he's on the outside of everything when he sees Leah leaving Nick's house.
Again, Simon thinks of himself as naturally nosy, but there's little evidence that he's particularly curious about his friends and their inner lives, something he's mostly discussed in terms of Nick. This suggests that Simon's assessment might not be entirely truthful, and that he'll need to reevaluate this part of his identity.