The white company do a ‘car seat’ blanket, it’s slightly smaller than their crib blanket. Cellular material with a silk trim, it’s lovely ☺️ but you can use any blanket that’s a suitable size there’s no rules 😇
Just use any small crib blanket over the top of the baby, it's not safe to add a blanket underneath the baby or thread the straps through because it affects the fit of the straps and hasn't been crash tested so there's no way of knowing if the seat will work as intended to protect your baby in a crash
Thanks ladies!
You can use any baby blanket, it doesn't have to be a particular kind. Just drape the blanket over the baby's lap over the car seat straps.