Rumors and Speculation:
* Boo Radley is a recluse: He has been shut away in his house for years, and no one sees him. This fuels the mystery and fear around him.
* He's a danger to children: There are stories about Boo being a "phantom" who can vanish into thin air, that he "drank lye" and is "not right in the head," and that he's a monster who will snatch children.
* He's a product of a dysfunctional family: It's known that Boo's father was a strict, stern man who was abusive to his children. There are whispers of "trouble with the law" concerning Boo's father and a drunken fight with his son.
* Boo's sister, Mrs. Radley, is a recluse too: The children are told to stay away from the Radleys, particularly Mrs. Radley.
Direct Observation:
* The Radley house is a creepy, dilapidated place: It's a symbol of fear and isolation, a place to avoid.
* Boo leaves mysterious gifts: The children discover small, wrapped gifts left in the knothole of an old oak tree on the Radley property, sparking speculation about who is leaving them.
What they don't know:
* The true story of Boo's life: They don't know why Boo stays shut up in the house, what happened to him, or what his true personality is. They only know the dark rumors and myths.
* The details of the Radley family's past: While they know bits and pieces about the family's behavior, they don't know the full extent of their history.
Throughout the novel, the children learn more about the Radleys and Boo specifically, but they are still largely in the dark about the specifics of the family's history. This ignorance contributes to the fear and mystery surrounding the Radleys and Boo, and their eventual discovery of the truth is a crucial part of the story's theme of overcoming prejudice and understanding the humanity of others.