How is Atticus different compared to Bob Ewell and Aunt Alexandra in the novel To Kill a Mockingbird?

Atticus is the novel's morally upright character who defends Tom Robinson in front of a prejudiced jury and town. Atticus believes in justice, tolerance, and equality. He is a compassionate individual who displays integrity and courage throughout the novel. Atticus loves his children and tries his best to impress certain positive values on them. Unlike her brother, Aunt Alexandra is prejudiced towards African-Americans and people of lower social classes. She displays contempt for the Finches' cook, Calpurnia, and refuses to let Scout play with Walter Cunningham Jr. because he is poor. Alexandra argues with Atticus throughout the novel and opposes his decision to defend Tom Robinson. Alexandra means well, but holds traditional Southern views regarding race and social class. Bob Ewell is Atticus' foil throughout the novel. He is the polar opposite of everything Atticus believes in. Bob Ewell is a racist alcoholic who lies while he is on the witness stand. Bob Ewell sexually abuses his daughter and neglects his children. Bob is a selfish, mean-spirited individual who seeks revenge on Atticus and his family.