Maybe his uncles presence can cause Patrick to feel uncomtarble or his uncle could say where he really comes from and cause maybe a chaos. For some reason Patrick really won't say where he comes from so this gives the reader the idea tat where he lives may not be the best place in town, or where he lives is not really a proper place to live.
As soon as they arrived, the students unpacked their bags and the teachers spoke with the park rangers. The students tents were set up with sleeping bags, flashlights, and bug spray.