My dd is 21mo. She is in single bed and the transition from cot to bed went fine. However, she has now decided that she is not ready for sleep until 9pm and if I put her to bed and leave the room she screams hysterically until I go back in, in some instances she has made herself sick. She has 1 nap a day for an hour and this is at lunchtime. I really need help/advice on how to get her to bed earlier and how to train her in to getting to sleep by herself. Please help. xxxxx