Early riser...

We have always had a pretty good sleep schedule. But these last couple of weeks have been awful. He keeps skipping his second nap (hasn't had a second nap at daycare in over a month) then is so tried and wants to go to bed early. But the main problem is he is getting up between 430 and 530 in the morning! What should I do? I think I am going to try to adjust his schedule this weekend but it is only Tuesday and that seems so far away!