hi is it normal for a 3 month old to not manage to last awake for more than 2 hours max after each napp/sleep, even when she has been asleep for a very long time (night) she still manages a mere 2 hours and then has to sleep no matter what!!! is this normal...surely by now she should manage to be awake for longer...thats what i understand from the books i have read...but any first hand experiences??