Mrs. Dubose is the meanest old lady ever.
Scout describes Mrs. Dubose as “plain hell” because she picks on the children.
Mrs. Dubose lived two doors up the street from us; neighborhood opinion was unanimous that Mrs. Dubose was the meanest old woman who ever lived. (ch 4)
Mrs. Dubose is described as “close on to a hundred” (ch 10), and she likes to insult people as they pass by. Atticus is always kind to her, and tells her she looks like a “picture.” He also tells his children to be polite.
When Jem loses his head and ruins Mrs. Dubose’s flowers because she insults Atticus, Atticus makes him go and read to her. He tells Jem later that Mrs. Dubose needs the reading because she is trying to wean herself off of morphine so she can die on her own terms. Atticus wants Jem to see what real courage looks like.
Considered by the children as "the meanest old woman who ever lived," Mrs. Henry Lafaette Dubose lives "two doors up the street" from the Finches. She often shouts insults at people who pass her house, and Cecil Jacobs, who lives at the end of the street, walks the other direction and goes around a long way in order to avoid her.
In Chapter 4, Scout states that Jem will not go past her house without Atticus beside him. But, one day after his twelfth birthday, his money is "burning up his pockets" and his desire to go to town so he can purchase a miniature steam engine and a baton for Scout is so strong that Jem braves passing the house of Mrs. Dubose. As expected, Mrs. Dubose shouts at Jem and Scout as they walk by, "Where are you two going at this time of day?"
When Jem tells her that it is Saturday, she retorts that it makes no difference what day it is and that she wonders if their father knows where they are. She then chastises Jem, saying that he will be sent to a reform school before the next week. Further, she tells Scout that she should be wearing a dress: "You'll grow up waiting on tables if you don't change your ways." And then, she adds an insulting comment about Atticus which enrages Jem, and in retaliation he damages her lovely camellias on the way home later.
Despite her cruel remarks, Atticus has Jem read for an hour a day to Mrs. Dubose. Some time later, Jem learns the reason for Mrs. Dubose's cruel remarks: She has been addicted to morphine.