She sounds a lot like my DS, he rarely slept anymore than 30 mins. It's starting to improve now that he's 1, but it's probably only 50% of the time that I get more than 30 mins and the longest he will ever sleep is 1.5 hours. By the sounds of things you're doing great, I think like the other ladies have said, the best thing you can do is just go with the flow. On days where she has a longer nap chances are she will go to bed later or earlier if she has one less that day. I try to be flexible with bedtime, for us we aim for between 6 and 7 depending on when he got up from his nap (mind you tonight it was nearly 8pm because he had a late nap). Personally I think it is far better to put them to bed that little bit later and make sure they get enough sleep during the day, than to stretch them out and let them get overtired, especially when they're really little. HTH