Quick Poll: Duvet or Gro/sleeping bag?

[DisasterZone]

DS is 9 mo and uses a 2.5 tog sleeping bag. Our room is usually 17deg at night, some nights it's 16 deg. I've noticed that in the cot he always sleeps on his front with his arms tucked underneath his body. He wears a long sleeved sleepsuit and a long sleeved top over that as recommended by grobag but I think he's cold at night? If I change his nappy his legs are cool, not toasty warm. He comes into our bed around 5am for a feed and cuddle and falls back to sleep in any position then and his limbs are warm when we get up. I've never used a duvet in a cot before and worry he's too mobile for it to stay on him.

What do you use and how does it work?

I used a sleeping bag until ds was 2 1/2 years. If his legs are cold then put pyjama trousers on him (does he have bare legs under the sleeping bag?).

co-sleeping under our duvet.

nope, legs are covered by sleep suit. I'm a bit paranoid about over heating and tonight I've got him in a warmer velour sleepsuit + top to see if that helps. I want to go and check him every 5 mins to make sure he's not too warm though! Daft I know.

I have found the grobag advice on what to wear to be very cautious, and my boys are / were cold if I dressed them as recommended. At 17 degrees I would have them in a 2.5 tog grobag, long sleeved vest and a sleepsuit (possibly a velour one if I thought the temp would drop). At 9 months overheating isn't, if I understand correctly, the same isssue that it is for very small babies, and I think the difference between putting a baby in a sleepsuit or not is unlikely to cause major overheating as it's not adding layers and layers IYSWIM?

Dd2 wears a full babygro and grobag. As long as they feel warm on the side of the neck don't worry if their arms and legs feel cool as their core body is fine

DS wears a long sleeved vest & pyjamas & 2.5tog grobag. If its particularly cold I would also put him in a velour sleepsuit instead of pj's.