First Cousin Once Removed – All Questions Answered

What is my dad’s first cousin to me? If my cousin has a kid, what am I to the baby? The answer to both questions is “first cousin once removed”.

This article gives simple and clear explanations of your family relationships. I also answer some other common questions around first cousins once removed.

Let’s start with the basics!

What Does “Once Removed” Mean?

I’m assuming you know exactly what a first cousin means. If you’re not sure, check out the explanation and diagrams in that linked article. So what about “once removed”?

“Once Removed” means that the family relationship is one generation away from you.

Your parents’ generation is one generation above you.

The children of your first cousins are one generation below you.

This illustration shows a family tree with the “once removed” relationship marked. Your first cousin’s child is once removed from you by being one generation below you.

family tree diagram of child of first cousin

That is not the only “once removed” relationship that you have. But it’s the easiest to understand.

Are you thinking – hey, isn’t my dad’s brother also once removed from me? Well, yes. But we simply call him your uncle. An uncle and aunt can only be one generation from you. The relationship is defined exactly by the word.

“Cousin” is a more general term. We need to add extra terms to define the extra relationship.

What Is A First Cousin Once Removed?

Your first cousin once removed is a close cousin who is one generation away from you.

The children of your first cousin are your first cousins once removed. They are one generation below you.

Your parents’ first cousins are also your first cousins once removed. They are one generation above you.

The picture in the previous section illustrates the relationship of the children of your first cousins to you. But we hadn’t mentioned how you are related to your parents’ cousins.

So, let’s take a closer look at one generation up.

What Is Your Dad’s First Cousin To You?

My Irish grandmother’s sister had eleven children. This gave my mother eleven first cousins in that family alone. But what are they to me?

They are not my first cousins because they are a generation above me. This means that they are my first cousins once removed.

Let’s illustrate this using your dad. The picture below highlights you and the son of your father’s uncle. Your dad is the same generation as his uncle’s son, which makes them first cousins.

You are one generation below your dad and his first cousin. This makes you a first cousin once removed of the highlighted cousin.

tree diagram of relationship to the first cousin of your father

The son of your first cousin once removed is the same generation as you. This is your second cousin.

We haven’t marked another “first cousin once removed” relationship in the picture above. But your second cousin on the right is a first cousin once removed of your dad.

First Cousin Once Removed Versus Second Cousin

Your second cousin is the same generation as you within your family tree. You both share great-grandparents and are three generations down.

When your first cousins are once removed, this means they are one generation up or down from a first cousin relationship.

Your great-grandparents are also their ancestors, but they are either closer to or further away from your common ancestors than you. They are either one rung up the family tree or one generation down.

Illustrated above

In the previous picture, we show both relationships. The bottom right family member is named as your second cousin.

We’ve also marked your dad’s first cousin – this is your first cousin once removed.

The Name Of The Relationship Works Both Ways

When you are first cousin once removed to family members, they are also first cousin once removed to you.

A lot of family relationships don’t work like that. You are niece to your aunt and grandchild to your grandparent.

But “first cousin once removed” is the same term for the relationship from both sides.

What does 1C1R mean?

You may see articles or charts referring to 1C1R.

1C1R stands for first cousin once removed.

Am I Blood Related To My First Cousin Once Removed?

Your first cousin once removed is a blood relative when you share common ancestors.

If the cousin relationship is through marriage, then you are not blood relatives.

Let’s take an example to explain. Let’s say that your aunt married a man who had children from a previous relationship.

Personally, I would call these children my cousins. Some cultures may not.

If they go on to have children, I would probably introduce the new additions to people as my cousins’ kids. I like to have an inclusive family!

Technically, they are not blood relations to me.

How Much DNA Do We Share?

First cousins once removed share amounts of DNA ranging from about 3.3% to 8.5%. The average percentage of shared DNA is about 6.3%.

This is about 100 to 980 centimorgans of shared DNA.

The reason for the range is that people inherit different amounts of DNA from common ancestors.

The amount passed down from your great-grandparents also gets smaller with each generation.

What Degree Is A First Cousin Once Removed?

You may see references in legal or genealogical texts about the degrees of “kinship” between cousins. You may also see terms like “collaterals within the fifth degree”.

Let’s explain these terms clearly. A “collateral” is simply a relative who isn’t in your direct line. This includes your uncle or aunt, or any of your cousins.

But what do “degrees” mean? This is a measure of the distance between you and your cousin. It’s a very simple count of the number of people between you and your common ancestors.

In this case, the common ancestors are your grandparents – who are the great-grandparents of your first cousin once removed.

There are two degrees (or hops) between you and your grandparents. There are three degrees from your first cousin once removed to her great-grandparents. You add these counts together!

A picture tells a thousand words! This diagram should make it clear.

What degree of relationship is a first cousin once removed?

First cousins once removed are at the fifth degree of relationship. They are collaterals within the fifth degree.

Can You Marry Your First Cousin Once Removed?

A small number of states in the United States do not allow marriages between first cousins once removed. At the time of writing, these are:

  • Kentucky
  • Nevada
  • Ohio
  • Rhode Island
  • Utah
  • Washington

State laws do change over time, so you should double-check with your state of interest.

A few more states only allow it when some conditions are met. For example, the woman may be required to be past the age of child-bearing.

It may surprise you to learn that the United States is somewhat unusual in having these restrictions. The U.S. is joined by China and North Korea in this regard. There’s a trio you don’t usually see joined together!

Many other countries have no restrictions on first cousins once removed. It’s legal in most European countries. Here are just some of the places where it is legal:

  • Canada
  • United Kingdom
  • Ireland
  • Australia
  • France
  • Japan
  • India

There are many more on the list.

Can You Get Married In A Catholic Church?

Even though it may be perfectly legal to marry your first cousin once removed, this question is whether a Catholic priest will preside over a church wedding.

Canon law is quite specific on the cousin relationship. Third cousins are fine.

Second cousins have to get a dispensation (approval) from the local Bishop. This can be requested by writing to the Bishop’s residence. The priest in your local church will advise you further.

First cousins have to get approval from the Vatican.

But what about first cousins once removed?

This is where things get a little confusing.

Canon law

Canon law is based on counting the number of generations away from the common ancestors for the two potential spouses.

Let’s say you want to marry your father’s first cousin. This person is two generations away from your great-grandparents. You are three generations away.

The next step is to add these numbers together to make five degrees of “consanguinity” (don’t get too caught up with the terms).

Canon law prohibits church marriages within four degrees. Your first cousin is four degrees from you (in the eyes of the Church), so this requires a dispensation.

But five degrees? That’s less of a problem! You should sit down with your local priest to discuss the matter.

I do advise t that you clarify the relationship with the priest beforehand. You don’t want him being alarmed if a neighbor casually mentions “first cousins” at the wedding reception.

Frequently Asked Questions

People ask specific questions in the context of their own families. I’ll run through these quickly as most of the answers are very similar.

What is my dad’s cousin to me?

Your dad’s first cousin is your first cousin once removed.

Your dad’s second cousin is your second cousin once removed.

What is my mom’s cousin to me?

Your mom’s first cousin is your first cousin once removed.

Your mom’s second cousin is your second cousin once removed.

What is my cousin’s child to me?

The child of your first cousin is your first cousin once removed.

The child of your second cousin is your second cousin once removed.

If my cousin has a baby then what am I?

If your cousin has a child then you are a first cousin once removed to the child.

Can I marry my first cousins daughter?

Your first cousin’s daughter is your first cousin once removed. Marriage is prohibited in a small number of states in the U.S.

Most other western countries have no restrictions on marriages between first cousins once removed.

Check the earlier section in this article on marriage.

Margaret created a family tree on a genealogy website in 2012. She purchased her first DNA kit in 2017. She created this website to share insights and how-to guides on DNA, genealogy, and family research.

3 thoughts on “First Cousin Once Removed – All Questions Answered”

  1. My brother shares 1321 CM with our supposed first cousin once removed – my Dad’s first cousin, the daughter of his father’s brother. We found out in 2019 thru DNA that our named Grandfather was not related. Then we found our actual relatives thru matches on Ancestry, and pieced together the relationships. I actually have contacted and become close with some of these relatives. I had 3 brothers and a sister do the Ancestry DNA and one brother and a sister share a very high percentage of DNA with new relatives, off the charts, although the rest of us are just high. Can’t find any recent intermarriage between close family so really puzzling. Only thing I see is our Quaker ancestors who did intermarry with cousins in the 1700s and 1800s. Would this be a factor in the high percentage shared now?

      • The main question I’m trying to answer is which brother out of a possible 3 is my grandfather. I assumed it was the brother that lived in the same building as my Grandmother the year (1931) my Dad was born. They weren’t a couple, both were married to others. However, I’ve found from new relatives that the other 2 brothers did visit periodically. Me and siblings are sharing off the charts or really high DNA % with one of the other 2 brother’s descendants, which includes tested children from 3 generations (several 1C1R, 2C, 2C1R 2C2R). The man we think is our grandfather had no children except our father. Thinking I’m maybe barking up the wrong DNA tree! Thanks for your reply


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