Well I think that the author's purpose for them moving around might be because they could work together as a team and rescue Dr. Shumway, Grady, and Uncle Bud. Also Sargent Webb. The reason why I picked that is because well they are the only ones who can save them. Grady is still in the cell. And Dr.Shumway and Uncle Bud and probley Sargent Webb.Another reason I think they were the ones chosen is because what if it was Grady? Grady wouldn't do much with his hurt hand in all. And the three adults might not get along well enough to work as a team. Especially Dr. Shumway and Uncle Bud.