Who is Christopher Swieteck from Okay for Now and what is their importance?

Christopher Swieteck is Doug's older brother and the middle child. He is known for his criminal activity and hanging around with thugs. Christopher beats up on Doug, picks on him and appears to be a mini-version of Mr. Swieteck. As the novel unfolds, however, Christopher reveals that he is not the criminal everyone says he is and that he only acts like he does after years of people expecting him to be that way.