Already discussed with some mumsnetters my worries about ds getting too used to naps in a darkened quiet room. He is 4.5 months now and I am not returning to work for a while yet, but I am concerned that when I do he won't be able to have a decent nap in a nursery enviroment. He gets very overtired and needs to spend afternoon being drive round or pushed in pram to catch up if he doesn't have a decent sleep around midday.