No. Submitting a release to an insurance company is a full, final termination of the claim forever. Nearly all insurance company releases include language that the document extinguishes the case forever even if new symptoms occur in the future that were unforeseen at that time.
If the niece were a minor at the time, her statute of limitations in New Hampshire would not have started to run until she turned 18, so she would have three years, until her 21st birthday to bring the claim before the statute of limitations kicked in. But your facts seem to indicate that a release was signed.
This is why significant settlements for minors must actually be approved by a court.
This is also one of those not-so-obvious concerns that do-it-yourselfers miss when handling their own cases. In wanting to close the case and get a check, the residuals or potential for long range issues are not thought of and not addressed. While the case is still open, potential long range consequences have to be documented and included.
Andrew Myers of Derry has law offices in Derry and North Andover. He is a member of the American Association for Justice and the New Hampshire Trial Lawyers Association. Send questions to email@example.com.