Has anything happened in that last 10 days , anything to upset him, a move , new school, house, family, friends ,siblings .What time does he go to bed , it maybe early for him , try putting him a bit later, read him some stories say around 8-8-30pm, does he watch anything scary on TV in the evenings ? I agree once you start to lie by him he will want you to, then you have to stop that. this may be simply a phase so be consistant , take him back to bed if he gets out, he could read for a while if he cant sleep .