Wow! Thanks everyone for the responses

It looks like this an age where it is pretty varied, so i guess we will stick to what is working for us at the moment. I think i just felt a bit bad that poor DD walked around with big black circles under her eyes today and wondered if she was getting enough sleep. I think i might reel back the 9pm bedtimes, these are usually the nights DF puts her to bed, eg. when i go to the gym or want to watch a show on tv and insist that he get her in there a lot earlier as we know it will take her longer than usual to go to sleep.