Rod Campbell makes books for babies and toddlers, the best known being Dear Zoo, which has sold over two million copies worldwide. All his books have simple text, often with repeating phrases, ideal for the pre-reader. He uses flaps and touch-and-feel elements when appropriate. Rod Campbell makes books for babies and toddlers, the best known being Dear Zoo, which has sold over two million copies worldwide. All his books have simple text, often with repeating phrases, ideal for the pre-reader. He uses flaps and touch-and-feel elements when appropriate.