However, not all sleep sacks can keep baby cool in warm weather and warm in cool weather! (blog.guguguru.com)
Wool is very breathable and will keep baby cool in summer and warm in winter. (change-diapers.com)
A fleece - lined infant car seat cover provides good insulation on those cold days while a breathable, sun - blocking cover can keep baby cool when the temperatures are high. (bestcarseathub.com)