If you have the proper relationship to the injured party and if the injured party is not able to pursue the case on his or her own. For instance, a minor child or an individual who has suffered such a bad injury that they're no longer competent, you may be able to sue on behalf of that person. If you're the parent and natural guardian, absolutely. If the child is a minor, meaning under 18 in New York, if the person is debilitated, then a court appointed guardian would be able to sue on behalf of the incapacitated adult. Usually, that would be a very close relative. If you are a close relative, you can apply to be appointed the guardian for that purpose and it should be granted.