In the juvenile detention center, Shawn eventually sets his sights on Robby after he defends an inmate, later mocking his relationship problems with Sam and Johnny, taking his pillow, ripping his book apart, and unplugging a computer as well as beating up Robby only with the help of two other guys.
Shawn seems to have a sense of family loyalty too, as he protected his younger brother Kenny from an former friend who had broken into his house, which is why he was sent to juvie. He eventually leaves Robby alone when they both respect each other for not giving each other away when they both had a fight. He also takes it upon himself to make Robby's life hell in the correctional in any way possible, such as pestering him about his problems with Sam and Johnny, vandalizing his belongings, or hitting him. Shawn is shown to be a violent, rude, ruthless and highly dangerous inmate who bullies other prisoners with sadistic pleasure.
