What is a great-aunt or great-uncle?
Short answerYour great-aunt or uncle is a sibling of your grandparent. You are their great-niece or nephew: the grandchild of their sibling. You share great-grandparents, and a full great-aunt or uncle shares about 12.5% of your DNA on average.
The family line, drawn out
Follow the highlighted line from you up to the shared ancestor and down to them.
How to work it out
Go up 3 generations from you to a shared great-grandparent, then 1 down to their child. That child is a sibling of your grandparent, which makes them your great-aunt or uncle. Some genealogists say grandaunt and granduncle instead; it means the same person.
Their spouse or partner is your great-aunt or uncle by marriage. Their children are your first cousin once removeds.
What to call each other
| Them, to you | You, to them | |
|---|---|---|
| Female | great-aunt | great-niece |
| Male | great-uncle | great-nephew |
| Anyone | great-aunt or uncle | great-niece or nephew |
Their family and yours
Relationships shift by one step for each generation. Here is how the people around them relate to you:
| Their child | first cousin once removed |
| Their parent on the shared line | great-grandparent |
| Your child sees them as your child’s | 2nd great-aunt or uncle |
| Your parent sees them as your parent’s | aunt or uncle |
| What they call you | great-niece or nephew |
Shared DNA
On average, full great-aunts and uncles share about 12.5% of their DNA. That figure is the expected value: it halves with every generation of separation, and real amounts vary from person to person. A half relationship (through only one shared ancestor instead of a couple) shares about half as much: 6.25%.
Let Family Trees name it for you
In Family Trees, open anyone’s page to see how they are related to you in plain words, or choose any two people under How are they related?. The app counts the shortest blood line through birth and adoptive parents, names step, foster and in-law relations too, and uses exactly the words on this page. It’s free for a family of up to 100 people. You can also try the relationship calculator here.
Questions
What is a great-aunt or uncle?
Your great-aunt or uncle is a sibling of your grandparent. You are their great-niece or nephew: the grandchild of their sibling.
How much DNA do you share with a great-aunt or uncle?
About 12.5% on average. Each generation of separation halves the expected amount, and individual results vary.
What is my great-aunt or uncle’s child to me?
Your first cousin once removed.
Is a great-aunt the same as a grandaunt?
Yes. Both words name a sibling of your grandparent. Great-aunt is more common in everyday speech; grandaunt is often used by genealogists and in legal documents.