Our 6 year old SWCAH daughter is the opposite.  Early to bed, early to rise!  Seems to tire quickly at the end of the day and really looks forward to her bed, however is up with the sparrows!  Having said that, I am also like that and another nonCAH daughter is like you and is a bit of a night owl and sleeps in next morning.  My husband is also like that as well.  Seems everyone is different.