How is Miss Foley's "nephew" Robert described?

Robert - Robert is the name of Miss Foley's real nephew who never appears in the book. When Will and Jim first see Miss Foley at the carnival she is looking for him, and later Mr. Cooger pretends to be him.

Mr. Cooger - Along with Mr. Dark, Mr. Cooger is in charge of the carnival. He is pure evil, and he pretends to be Miss Foley's nephew Robert in order to get her to ride on the carousel. Mr. Cooger also tries to get Jim to ride on the merry-go-round, and if not for Will he would have succeeded. Although he is dangerous and cunning, Mr. Cooger is a threatening possibility for most of the book since he is too old to do anything after Will messes up his carousel ride.