What is Lee's purpose for re-introducing Boo Radely in chapter 26?

THe children have endured the trial and are now back in school. Boo, early in the book, had been a source of fear and almost terror. However, as the children developed a kind of relationship with him, they grew less fearful. Scout would actually like to meet him. Her thoughts, however, are consumed with the real danger of men like Bob Ewell, who threats and malice toward her father are much more real than the fear of Boo ever was.