A.T.
I highly recommend a book called healthy sleep habits, healthy child. It tells you at what stage what to expect. It sounds like she may be sleep deprived. If they don't get enough sleep, they will actually be up more often. (It is scientifically proven. Stress hormone levels go up, and then whammo they get there second wind.) Of course, make sure nothing is going on medically before you try letting her cry....for your own benefit. She is way too old to be doing this. She should be sleeping about 10-12 hours at night then two naps during the day. Bedtime should be no later than about 830.Please read this book. People will give you all sorts of whacko advice that just isn't true, and meanwhile you will be losing sleep.