One day, Mrs. Dubose, an old woman who harasses Scout and Jem whenever they walk past her house, condemns Atticus for defending Tom Robinson. Jem, enraged, rips the flowers off her camellia bushes.
Though Jem is growing up, he isn't an adult yet: he can't control his emotions.
As punishment, Atticus makes Jem go and read to Mrs. Dubose each afternoon. Scout goes with him. At first, each reading session is cut short by Mrs. Dubose's strange fits, but over the month the sessions get longer and the fits slowly disappear. Soon after the reading sessions end, Mrs. Dubose dies. She leaves Jem a single white camellia flower. Jem is horrified, but Atticus explains that Mrs. Dubose was addicted to morphine and the reading sessions helped her kick the habit before she died. Even though Mrs. Dubose ridiculed Atticus for defending Tom Robinson, he calls her the most courageous person he ever knew, a person who knew she was beaten and still fought no matter what.
Mrs. Dubose and her battle with her morphine addiction allow Atticus to teach Jem and Scout a lesson about both courage and human dignity. Yes, Atticus admits, Mrs. Dubose is prejudiced. But she is also courageous; fighting a battle against morphine she knows is both right and probably a lost cause. Atticus wants his kids to realize that courage isn't strength or skill with a gun, it's standing up for what's right no matter what.