Was reading this thread and thinking...I WISH my DS would just happily play in his room at 3am. Instead, we get the night visits...sometimes up to 6 times a night. And yes, DS was a perfect sleeper until about three months ago too
But, not sure I want a feral little boy in place of my gorgeous son, so maybe you ladies have it equally as bad!

No advice, but I do hope your DS's aren't as stubborn as mine. We've tried praise, stickers, pocket money, bribes for afternoon tea from the bakery, the silent treatment, grumpy Mummy and Daddy, nice Mummy and Daddy, Grow Clock, countless stories about little boys/girls/animals who stay in their beds all night, pleading(!!!!)....with zero result! He says he doesn't want the reward that badly and would rather keep coming into Mummy and Daddy. What do you say to that?

Just a thought....can you somehow make it impossible for him to turn on the light? If its too dark, would that deter him? Any luck with stickers or some other positive reward? A friend got her son to stay in bed by enforcing a nap during the day (or quiet time in the afternoon) if he gets up during the night.

Would love to hear how you get on