Winter Coat

Lauren
I live in Ohio and it is starting to get pretty chilly. My son is 6 months but in 12 month clothes. What are you moms doing for a winter coat? I know they say they shouldn't wear them in a car seat. Is that just infant or convertible too? He is in his convertible car seat so I can't buy those covers for the infant car seat. Just wanted to know what others were thinking. Thanks!