Jem and Scout always hated walking by Mrs. Dubose's house, but it was impossible to get to their home without passing her on her porch. She cried out and insulted them whenever they passed by, but when she told Jem that Atticus was "no better than the niggers and trash he worked for," it was too much for the boy. After taking Scout to the store to buy her a new baton, Jem took the baton and returned to Mrs. Dubose's back yard, where he destroyed all of her camellia bushes. When Atticus found out, he directed Jem to go and have a talk with Mrs. Dubose. Jem came home with bad news.
"She wants me to come every afternoon after school and Saturdays and read to her out loud for two hours."
Atticus' response was "then you'll do it for a month."
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In Harper Lee's To Kill a Mockingbird, Jem and Scout pass Mrs. Dubose' house one day, and the old woman insults Atticus. Passing by her home again later—when no one is on the porch—Jem destroys all of the buds and blooms on Mrs. Dubose's prized camellias.
When Atticus finds out, first he makes Jem returns to Mrs. Dubose and faces up to what he has done. Then Jem must spend time each day after school reading to Mrs. Dubose. (Scout chooses to accompany him.) It often seems that Mrs. Dubose is not listening, and they are released only when an alarm clock rings in her room. As the days go by, the time they spend there gets longer as they wait for the clock to ring. Finally, there is no ringing—Mrs. Dubose dismisses them.
It is only later that Atticus tells Scout and Jem that Mrs. Dubose was trying to fight off an addition to morphine, a pain medication. Each day she lasted a little longer until she no longer needed the medication. Even though she was still fighting a painful disease, she chose to live the rest of her life on her terms, without being dependent upon drugs. She was a tough woman, and not very nice, but she was brave and determined. After her death, Atticus says that Mrs. Dubose was the bravest woman he had ever met—high praise from Atticus.