In town, Scout and Jem hear lots of muttered comments about the Finch family. Scout hears one that mentions rape and remembers that she never asked Atticus what rape is. She asks him that night and when he tells her, she ends up telling him all about her trip to Calpurnia’s church. Aunt Alexandra is shocked that Scout and Jem went to Calpurnia’s church. Scout asks Atticus if she can visit Calpurnia on Sunday, but Aunt Alexandra forbids it. Scout spits that she didn’t ask her. Atticus forces her to apologize, and Scout leaves. She listens from the hall as Aunt Alexandra scolds Atticus for keeping Calpurnia, but Atticus insists that Calpurnia is a member of the family and has done a great job with the children.
It is somewhat unclear exactly why Aunt Alexandra is so offended by Calpurnia’s presence, as she is, according to Scout, a fine cook and clearly cares for Scout and Jem. It’s likely that Aunt Alexandra is simply trying to not come out and say outright that she doesn’t think a black woman should be raising her niece and nephew. Atticus’s defense of Calpurnia shows that he believes it’s his job to treat Calpurnia fairly and respectfully, which in his eyes, means defending her to Aunt Alexandra and keeping her employed in their household.
Upstairs, Jem gravely asks Scout to not annoy Aunt Alexandra. This angers Scout, but Jem insists that they need to think about how preoccupied Atticus is with the Tom Robinson case. His superiority angers Scout. When he threatens to spank her, she calls him a morphodite and they start a fistfight. Atticus separates them, asks who started it, and tells Scout that she only has to listen to Jem if he can make her do so. This enrages Aunt Alexandra.
Again, Scout clearly still has no idea what “morphodite” means—she’s hurling the insult at Jem for no reason other than the suspicion that it’s not an especially polite thing to say. Atticus’s method of dealing with the fight acknowledges that his children are individuals who should learn on their own to deal with conflicts, while Aunt Alexandra’s reaction implies that she thinks Atticus needs to be more of an authoritative parent.
As she gets into bed, Scout steps on something that she thinks feels like a snake. She asks Jem to come investigate. He pokes a broom under the bed and Dill emerges. Scout fetches him milk and cornbread when he asks and Dill tells a far-fetched narrative of how he got here, followed by the truth: he has run away from home, and took a 14-mile train ride from Mississippi to Maycomb. Jem is concerned that Dill’s mother doesn’t know where he is, and he calls for Atticus. Dill goes white. Atticus pleasantly tells Scout to get Dill better food and calms Dill when he hysterically threatens to run away again if they make him go back. Atticus assures him that he just wants to check with Miss Rachel if Dill can stay the night. Jem stands alone and says he had to tell.
When Jem chooses to alert Atticus to Dill’s arrival, it makes it clear that he’s beginning to shift from child to adult. He’s able to understand that Dill’s parents are surely very worried and need to know where he is, something that Scout and Dill, as young children, don’t find especially compelling. This begins to situate Jem as significantly more mature and empathetic than his younger peers, and given Scout and Dill’s idolization of him, provides hope that they, too, will grow up to emulate his thoughtfulness.
Dill eats and then survives Miss Rachel’s scolding. She allows him to stay. Aunt Alexandra sends the children to bed and since things seem okay, Scout and Dill decide to be civil to Jem. Scout wakes up in the middle of the night when Dill crawls in with her. She asks why he ran away. Dill explains that his new father isn’t interested in him, and his parents ignore him. Scout tells him that life would be awful if his parents were too interested, but she begins to wonder how things would be different if Atticus didn’t want her around. Dill suggests that he and Scout buy a baby. Scout asks if Dill has any idea why Boo Radley never ran away. Dill wonders if Boo doesn’t have anywhere to go.
Even if Dill might not be on par with Jem in terms of maturity, his assessment of why Boo hasn’t run away shows that he’s more than capable of thinking critically about the way Boo doesn’t fits into society. Dill is continuing to evaluate his prior fear and prejudice against Boo and against others, while also potentially coming to recognize just how unwelcoming Maycomb is to those who are different.