DS6 loves the Rosco Riley series and has now found Captain Underpants and he loves it...how can you not love attacking toilets with teeth :-) He also loves any of the Roald Dahl books...his favorite movie when he was 4 was Charlie and the Chocolate Factory. I am thinking about starting him on some of my favorite series (Lion, Witch, Wardrobe...Prince Caspian) and these are way out of his league but was one of my favorite series of books...Madeleine L'Engle's books - A Wrinkle in Time, A Wind in the Door, A Swiftly Tilting Planet, Many Waters, and An Acceptable Time....I LOVED her books.