Who did Bryon's mother ask him to visit? What did Bryon learn about this person?

In Chapter 2, Bryon and Mark visit their mother in the hospital, and she tells them to go over and visit the boy in the next room because nobody has come to see him. Initially, Bryon refuses to visit with the boy, but Mark decides to go into the room to talk with him. After Bryon gets something to eat at the snack bar, he peeks into the boy's room to look for Mark. Although he doesn't see Mark, the boy introduces himself to Bryon. The boy's name is Mike Chambers, and he tells Bryon the story of how he got beat up by a group of black guys who hospitalized him. Mike says that his friends were picking on a harmless black girl in a convenience store, and he stood up for her in front of them. He then offered the girl a ride home, and she reluctantly agreed to let him drive her home. When Mike dropped her off in a black neighborhood, a group of black guys surrounded his car and saw that the girl had been crying. They dragged Mike out of the car and asked Mike if he hurt her, to which Mike replied that he did not. One of the men then asked the girl what she wanted them to do with Mike, and she said, "Kill the white bastard" (Hinton 17). Mike Chambers tells Bryon that they almost beat him to death, and the story profoundly impacts Bryon.