What Is an Eighth Cousin?

Have you been tracing your family history and come across distant cousins you have never heard of? Perhaps you are coming across the phrase “eighth cousin” and aren’t sure what that is or who they are?

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When it comes to finding distant relatives, you open a whole new can of worms.

Not only do you fill in gaps on your family tree and meet relatives, but it throws you into a world of phrases and terms you might have never heard before. And an eighth cousin is one of these phrases. 

Many of us will never have heard of an eighth cousin before and won’t know what it means or what their relationship to us could be. So we hit the internet, searching, and scrolling, but never finding the answer we need.

It can be frustrating and leave many of us wondering how we can complete our family trees without this knowledge. Well, no more—read on for answers to all of your questions about eighth cousins!

What Is An Eighth Cousin? 

Let’s get straight into it! An eighth cousin will share great-great-great-great-great-great-great grandparents (so that’s seven “greats”). An eighth cousin comes from another child of your seventh great-grandparents than the child you come from—so those two children were siblings.

Now that we have covered what an eighth cousin is, let’s take a closer look at this relationship to learn even more about it!

What Does Eighth Cousin Once Removed Mean?

The term “once-removed” means that person is separated by one more generation than you are from your most recent common ancestor or “MRCA” for short.

So, your eighth cousin once removed is your eighth cousin’s child, and, you are the eighth cousin once removed of your parent’s eighth cousin.

In geneaology, you might see “eighth cousin once removed” written as the abbreviation, 8C1R. This could be on family trees or as a way that specialists will list your relatives and your relationship to them. In the world of ancestry and family history, there are lots of abbreviations!

Are Eighth Cousins Considered Distant Cousins?

It might seem a little obvious, but yes, your eighth cousins are distant cousins. Generally, we wouldn’t refer to our eighth cousins as distant cousnis in everday conversation, since they are just SO distant; however, for the purpose of researching your family tree, they are distant cousins.

Larger families were the norm in previous generations, so your seventh great grandparents would likely have had at least a few children that could generate eighth cousins for you to find. 

Fourth cousins and beyond are usually referred to as distant relatives. Of course, if you have a small immediate family but a larger extended family, you might classify these distant cousins as close cousins.

Just because they are labeled as distant relatives does not mean you need to treat them as such! 

How Many Degrees Are Eighth Cousins Separated By?

There is a large degree of separation between eighth cousins—a whopping eighteen degrees! For reference, there are only four degrees of separation between first cousins.

So how do we work it out? Simply start from ourselves and count up to the MRCA (remember: the most recent common ancestor), which would be the seventh great-grandparents. Next, we count the generations back down until we hit our eighth cousin on a family tree.

Following this method, you will count nine generations up to your seventh great-grandparents (MRCA), then back down nine generations to get to your eighth cousin, which would equal eighteen total degrees of separation.

What Is the Meaning of Half-Eighth Cousin?

While researching your family, you might have come across the phrase half-cousin. Half-cousins are those who share one relation instead of a set, like a set of grandparents. (For more clarification, we have a helpful guide on half-cousins as well.)

This would mean a half-eighth cousin is someone who shares just one of the two seventh great-grandparents with you. This happens when your seventh great-grandparent has a child with another partner, making their children half siblings.

Given how long ago this would have been, the likely causes are being widowed or having an affair rather than a divorce, which was uncommon back then. Their children (your sixth great-grandparents) would be half-siblings, sharing only one parent rather than two.

How Many Eighth Cousins Does Each Person Have?

Get ready, because we are going to shock you with the numbers. According to a statistic, you might have 590,000 eighth cousins! Yes—over half a million people are eighth cousins and distantly related to you (see why they are referred to as “distant cousins”?).

Remember, family trees grow exponentially, so while this seems like an almost impossible amount of eighth cousins, it’s really not that crazy!

These are distant relatives, but relatives nonetheless! It would be incredibly challenging to find all of these eighth cousins, especially if the family moved away and you are battling with foreign languages or international rules surrounding access to information.

But these numbers go to show that we all have a large family, even if it is distant! 

Given that there are so many degrees of separation between you and any eighth cousins, it is unlikely that you will share a blood relation with them.

Remember, being related through DNA and being genealogically related are not the same thing. There is roughly a 0.24% chance of being DNA matches.

However, since we all have over half a million eighth cousins, even at that small percentage, you can still find a decent amount of them by taking a DNA test. 

How Do I Find My Eighth Cousins?

So how can you track down these distant cousins? Well, the two methods you can use are taking a DNA test and by doing genealogical research. 

Since a decent amount of your eighth cousins are likely to show up on a DNA test as a match (despite being a small percentage of the total number of eighth cousins), you should still be able to find some through this method.

For the best results in your research, you will want your test to be done with a well-known DNA-testing company. A good site to use would be Ancestry, which currently has the biggest database of DNA customers, giving you a good chance of finding some matches!

By getting your test done with a common servicee like Ancestry, you’ll likely be able to find thousands of DNA matches to distant relatives and cousins.

You can also find eighth cousins with the second method: by doing genealogical research. You can find others who are researching your shared distant relatives through public family trees which are also available on sites like Ancestry, but note that these may not provide you with as thorough results as DNA testing would.

If you have a relative appearing on a public family tree, then chances are you are distantly related! It’s worth having a look to see what’s out there. 

Final Thoughts 

And there you have it, an eighth cousin is someone you share 7th great-grandparents with. These distant relatives can be found with DNA testing or genealogy research and can help you fill out your larger family tree. With so many distant cousins out there, why not draw up a family tree and see who you are related to?

Use these genealogy forms to stay organized as you discover your family history!

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