Zhai has always been an early riser.... I have tried every method i can think of to get him to sleep a little longer. At one stage he was getting up at 5:30. I make him sit/lay in our bed till Jett wakes up. (thats only about 1/2 hr not even that sometimes).
Zhai is a really light sleeper from about 5:30am so maybe DS#1 is hearing DS#2? Are they in the same room?