Now that i'm watching the Percy Jackson And The Olympians series I wonder how the idea for the book series came about? I did hear that Rick Riordan had written the series for his son because his son is a huge fan of Greek Mythology and he decided a book series based on his son's obsession with Greek Mythology would be the ticket for a bestselling kids book series. Also was Rick Riordan a famous author before the Percy Jackson And The Olympians series? And what was his first book?