G.C.
I concur with just about everyone else: there's not much you can do with an early riser but go to be earlier yourself. My almost 4 year old ALWAYS gets up between 5:30 and 6:15 every morning no matter what time she goes to bed - whether 7 or 10 p.m. So, we put her to bed by 7:30 or 8 to give ourselves some quiet time at night. She has only slept until 7:30 one time in her entire life (and I kept checking on her because I thought something might be wrong!).
She FIANLLY knows what 6 o'clock looks like on her digital alarm clock, so isn't allowed to wake me up until then. But, it doesn't always work. One thing we did try that worked for a while (before she knew her numbers) was to get one of those songbird-type alarm clocks. We set the alarm for 6 a.m. and she wasn't allowed to leave her bed until the "birds woke up". The thing we are doing right now is that she doesn't get a bed time story if she wakes me up in the middle of the night or before 6 a.m. It's harsh and there are lots of tears and complaining about not getting a story before bed, but it seems to be working and I'm getting a little more sleep.
I'm sorry to tell you that if you've got an early riser they will probably ALWAYS be an early riser. I'm a case in point. I remember as a kid in elementary school getting up at 5 a.m., getting my own breakfast and watching old black and white reruns on t.v. By highschool, I was on the bus to school before the rest of my family even got out of bed! And in college, I crammed for tests and wrote papers by getting up at 5 a.m. instead of staying up all night. A night owl I'm not even now! :-) Good luck!