Rather than buying a huge snowsuit or baby parka, consider adding thin clothing layers underneath, topped off with a light winter coat or fleece snowsuit, to provide enough warmth without making baby sweat. (thespruce.com)
Also, unlike some other sleep bags, there is no synthetic filling which can make baby sweat and overheat. (woolino.com)
If you notice your baby sweating or breathing rapidly, he or she may be too warm. (twiniversity.com)