At first Lex thinks the guy who saved him – Clark – is his own age; he certainly looks like he's about 20. Even when his dad comes to pick him up Lex doesn't think much of it. It isn't until later, when he's looking into the Kent family that he finds out that Clark is fourteen. Lex tries to convince himself that this could be good. He had never really gotten the chance to be a big brother, and now Clark can be the little brother he' always wanted. His extremely attractive little brother. Yup, this was going to be great.