Rufus just doesn't stand a chance when it comes to blending in at his new school. His thick accent and small selection of clothing make him a target of the other children. In chapter 3, Kenny and Rufus have become friends, though Kenny does not advertise this to his classmates.
One day on the bus, Larry Dunn comes up to Rufus and his little brother Cody and makes a derisive comment about how the brothers share their clothing. The whole bus starts laughing at this. Despite his better inclinations, Kenny starts laughing too. Immediately Kenny knows that he made a mistake and stifles his laughter.
After this incident, Kenny and Rufus's friendship starts to fray. Instead of spending so much time together, Rufus and Cody start avoiding Kenny. When Kenny tries to play with his friend, Rufus tells him that he thought Kenny was different and that he doesn't want to play with him anymore. Kenny is devastated by this and regrets his reaction on the bus more than ever. After several days without his friend, Kenny is feeling really bad. It takes an intervention by Momma to heal the schism between the two boys, but they eventually make up and resume their friendship.