Putting him to sleep later might actually be counterproductive! There are some tips here, but one of the causes mentioned for early rising is too late of a bedtime:
"Skipping naps and putting your child to bed later will cause early rising-I know it’s not logical, and you and I would never do that – but it is true!"
http://sleeplady.com/child-early-rising/rise-shine-the-early-waking-toddler/
I liked the tip on keeping the room dark in the morning :) When my daughter wakes up and sees sunlight, she blinks a few times, looks around the room, smiles at me, and just like that -- she's up!
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