You are right in principle, but the mansion does not seem to be owned by an uncle, and there is no indication they were related at all. He is to referred throu

You are right in principle, but the mansion does not seem to be owned by an uncle, and there is no indication they were related at all. He is to referred throughout the book as "the professor". The Pevensies are definitely middle class kids. The sort of kids an academic like Lewis would have known in real life, and probably reflecting the real Lucy's family's circumstances.