My 18 month old DS is wearing a 1.5 tog sleeping bag (from Sainsburys) in size 18- 24 months. I've just been to check on him and he is sweating. Room is 21.4. So I'm trying to find him a lower tog but cant seem to find a lot online. Does anyone have any recommendations for brands? I've seen slumbersac but they seem quite expensive and wondered if it is worth it. Thank you!