The two children of Atticus Finch, Scout and Jem both dearly love their father, Calpurnia and Miss Maudie; however, they also have other strong feelings. They fear the "haint" in the Radley house across the street, and they will not allow anyone to speak badly of or bring harm to their family. For instance, Scout fights her cousin Francis for calling her father names, while Jem cuts off the tops of Mrs. Dubose's camellias.
But, for all her pluck and hoyden ways, Scout is yet a girl, and still a naive child. She does not understand how the men can come as a mob and harm her father as he guards the jailhouse door, but with her fierce, instinctive loyalty, Scout follows her father's advice and talks to Mr. Cunningham about "what interests him." When she does, he becomes embarrassed about what he is doing to Atticus, who has always treated him kindly; so, he orders the others to leave, and the men depart.
Because of her young age and ingenuousness, Scout's brother must explain to her the contradictions of life, while she tries to fight her way out. For instance, he tells her about mixed children such as those of Mr. Dolphus Raymond; he demonstrates that Dill must be responsible and respectful to his mother. But, he needs his father to explain to him how Tom Robinson could be found guilty of harming Mayella. Yet, Jem is better able to reason than Scout. In Chapter 6, for example, Jem wants to go back to the Radley's for his pants that have caught on the fence, after Mr. Radley comes out with the shotgun, but Scout thinks it is a foolish idea.
I was desperate: "Look, it ain't worth it, Jem. A lickin' hurts but it doesn't last. You'll get your head shot off, Jem. Please..."
He blew out his breath patiently. "I—it's like this, Scout," he muttered. "Atticus ain't ever whipped me since I can remember. I wanta keep it that way. […] We shouldn'a done that tonight, Scout."
Jem is ashamed and does not want his father to know what he has done; he also reasons well, and instructs his sister that their actions were foolish and wrong.