Jean Louise finds a racist pamphlet in her father's office: The Black Plague (8.16). It's not about the bubonic plague. Nope, it's about black people.
She learns from Alexandra that Atticus and Henry have been attending a County Citizens' Council, which is basically a meeting for white men to go to and talk about the evils of black people and integration.
Jean Louise has to see it for herself.
Sure enough, Atticus and Henry are both there, sitting down as a man named Grady O'Hanlon spouts his racist beliefs.
Jean Louise is shocked. She remembers the time her father defended a black man, and won him an acquittal. (Did you notice that this is different from To Kill A Mockingbird, where Finch does not win his case?)
Seeing Atticus at this meeting makes her sick to her stomach...obvs.
She staggers from the courthouse, and she stumbles through the streets until she finds herself at the ice cream shop where her old house used to stand.
The man who runs the shop recognizes her and offers to give her a free serving if she guesses his name.
But...she doesn't know his name.
She orders a container of ice cream and takes it around back to be alone with her ice cream and her disgust with her father.