I wouldnt be too worried at his age... I was definately doing the same with Aidyn. He would go down at about 6 or 7, then would be up again soon afterwards, and then he would go to bed at the same time as us... this ensured that I would at least get some sleep! I cant say I remember having any difficulty with changing his routine as he got older. I think once he was sleeping through for more than 8-10 hours I moved his bedtime to earlier in the evening.