Cookie, this won't help you (no toddler sizes), but I thought I would post a coat that might be OK in a car seat. Land's End has a new (I think) hooded jacket called the
Lightweight Packable Jacket for $69. It says that it will pack into its own pocket so that seems promising. If you wait for one of their 30% off sales, that would make it $48.30.
FEATURES
TEMPERATURE RATING: WARMER 5°/35° F Learn more
Packs away into its own pocket
Water- and wind-resistant nylon shell
Polyester lining
100 grams of Primaloft® insulation in hood, sleeves and body
Full-zip front with comfy chin guard
Machine wash
Imported