I know that a lot of people will be opposed to this idea but a dr recommended this to me with my first DS and it made the world of difference. We use a 4 fin oil heater in their rooms.It's the smallest one you can get and we put it on before we go to bed. It stays on all night and just takes the chill off the air. I can honestly say it does work for us. I didnt turn it on a few nights ago and we had a shocking night with waking. DS also won't sleep in a sleeping bag and won't keep the covers on. We usually don't turn it on though until about 10pm or 10.30pm and usually only set the thermostat to half way. If you feel comfortable doing this I would give it a try because it is starting to get cool in the night.