@Scott Kimminau if this was a serious case they would be waiting to write a demand letter until she could demonstrate actual medical costs and damages. Many years ago, I was served with papers for a medical claim from a traffic accident about a week before the 4 year time limit after the accident closed.
Turned out the gentleman that brought the claim was heading back to work on his first day back from disability when he claimed he hurt his neck in our accident, allowing him to go back on the clock. Go figure.
We objected to our insurance companies offer to settle for short money as inadequately protecting my interests in terms of rising rates and having to report an adverse civil judgement. So we went to deposition and....they wrote them a small check with some kind of "not my fault" document and the guy disappeared and they never dinged my policy.
Not strictly relevant but maybe educational. Sounds like a fishing expedition. You are the first line. Maybe she should sue her Mom.