If the person is a relative and the person has no living close relatives, you can request permission to do the ordinances. If you do not know whether the person has living close relatives or if you cannot contact them, please do not request permission. Instead, do more research to find the closest living relative or to prove that all close relatives are deceased.
The closest living relatives are an undivorced spouse (the spouse to whom the individual was married at death), an adult child, a parent, or a brother or sister.
If the person has no close living relatives to give permission, you can still request permission to do the ordinances. Please be prepared to provide evidence that all close relatives are deceased.
For more information on this topic, please consult the Church’s General Handbook: Serving in The Church of Jesus Christ of Latter-day Saints, 28.1.
Related articles
How do I request ordinances for an ancestor who was born in the last 110 years?
Can I request proxy temple ordinances for a friend?