Ever heard of "coat compression"? It's what happens to bulky, fluffy, puffy clothing, most often outerwear, when it gets squished - for example, by an infant car seat harness. Suddenly, there's lots of space between the harness and the baby who's wearing the coat - enough space for the baby to slip through.
Experts are telling parents to "strap before you wrap" your baby in the car seat. In other words, put your baby in the seat, buckle him up, wrap a blanket around him for warmth, and put the jacket on the baby when you get out of the car. Otherwise, if you strap your puffy bundle of baby into the seat and there's an impact, the straps can compress that puffy jacket or snowsuit and the baby will no longer be tightly held by the harness - especially if the baby's coat has room to grow.
If you or your baby don't like the "strap and wrap" solution, experts say to look for an outer garment or bag that has slits for harness to pass through.
How do you keep your baby warm in the car?