Jodles - my only suggestion would be could you take her for a walk in the pram or drive in the car at 4pm? I used to do this with DS and he would either nap, or just lie there awake but resting. I would find that this would let me stretch out his bed time to atleast 7-7.30pm. Or how would she go if you put her down in her cot at 4 but woke her after half an hour?