My ds is a great sleeper, but the last 2 nights have taken the biscuit. He normally goes off between 6.30pm and 7pm and will wake any time from 7am onwards. Last 2 days he hasn't woken until 10am - in fact today I had to go in and wake him. He dropped his daytime nap when he was about 20m so is always shattered by bedtime. He is not ill, apart from a bout of constipation. Does anyone have any similiar experiences ?