A friend of Max. Rex was found as an infant by paleontologist Dr. Owen, in an egg-like container within a dinosaur exhibit in New York. Rex. Now 12, has been left with Max and his family (Dr. Owen being a family friend) while his father goes searching for fossils. Rex's partner is a Carnotaurus called Ace. Rex is a good hearted boy, but extremely short-tempered from the beginning. Rex also likes to play the violin.

(Source: Wikipedia)