As an insurance person, what I would do is one of two things: ask them to put in writing that they are not willing to pay for a replacement car seat that was involved in this collision or send them a certified return receipt letter confirming conversions with so and so claims handler and so and so supervisor on such and such dates confirming that Geico is unwilling to pay to replace a car seat that was involved in this collision and thereby they will be assuming all risk associated with any injuries sustained by any occupants of that car seat in a future collision whether you are their insured or not because the car seat manufacturer will not assume any liability for a car seat that was involved in a previous collision. Be very specific in dates, names, everything. And send it certified return receipt. Trust me. If I got that letter, it’s cheaper to send you the $100 or however much a new car seat is than to have that letter sitting on my supervisor’s desk. The potential exposure is so much more than the $100. If they say no, you can also file a complaint with the Illinois Department of Insurance. It’s common knowledge to replace a car seat after an accident. Duh. Good luck.