DS (5) has always been an early riser. I don't think the warm weather and light mornings are helping but we've been seeing 4.30-5am wake ups for the last week or 2... he's a noisy bugger too as in 'I CANT SLEEP! CAN I GO DOWNSTAIRS/HAVE A DRINK' and so on. Then our 20 month old starts to wake (who then ends up hideously grumpy as he's more of a 7am kinda guy), so we end up having to be downstairs monitoring the younger one.
Does anyone have any thoughts, and more to the point any success with gro-clocks? I've put off buying one until now as I can just imagine him ignoring it. But feel that he's at the age it might work along with a small reward of some sort. It doesn't help that I think he needs the loo (cue more clattering and flushing) around that time, but I guess there isn't much we can do about that. 
All help gratefully received!