What Is the Meaning of Third Cousin Once Removed?

Families are complex. Especially large families. If you have ever done any research into your family history, then you have probably stumbled across a couple of family members that you hadn’t even realized you had.

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Likewise, you might have stumbled across connections in your family that you didn’t even know existed. 

The terms used to describe family members can often be confusing.

Close relatives are easy to understand, you have parents, siblings, and grandparents, and uncles and aunties. But, when it comes to cousins it can really get confusing. Sure, first and second cousins are easy to understand.

However, when it gets to third cousins, and cousins that have been “removed”, it can be difficult to understand.

One relation in particular that confuses people is “third cousin once removed”. In this guide, we’ll be taking a look at what this relation is, and lots more. So to find out, keep on reading. 

What is a Third Cousin Once Removed?

First things first, let’s take a look at what a third cousin once removed is. As the name suggests, a third cousin once removed is a cousin of yours. So, you and your third cousin once removed are related through your great-great grandparents.

Who are your third cousins once removed? Find out with a DNA test!

If you and your third cousin share the same number of generations between you and your great-great grandparents, then you are simply third cousins. If there is not the same number of generations between you, then that is when the “removed” comes into play. 

So, a third cousin once removed will be the child of your third cousin. You and your third cousin are of the same generation, but their child will be the generation below you. It is this extra generation that makes them your third cousin once removed.

Alternatively, you will be the third cousin once removed of your parent’s third cousin. 

It can be pretty complex to understand cousins once “removed” comes into play. But the “removed” comes into force with any offspring past your third cousin. This means that you can have a third cousin once, twice, or third removed.

It is these additional numbers that just make things even more confusing. So, let’s take a look at how to discover how removed your cousin is. 

Finding Your Third Cousin Once Removed

As we say, families are complicated. So, finding your third cousin once removed isn’t always the easiest thing to do. But, most of the time, you can figure this out by speaking to your potential relative, and working through the following steps. 

The first thing that you need to do in order to calculate how removed your cousin is, is to figure out who your common relative is. Once you have this person in mind, you both have to calculate how many generations there are between you and this person. You might not always have the same number of generations between you and that relative. Once you figure it out, you should use the relative that is the closest related to you in terms of generations. 

With that person in mind, calculate the number of generations between you in numbers. Then subtract ‘1’ from that number. Then compare your numbers to one another. If you are 4 generations below the common relative, and they are 6 generations below the common relative, this will make you third cousins twice removed. That is because 4-1 equals 3 and 4-6 equals 2. 

Who are your third cousins once removed? Find out with a DNA test!

Figuring Out How Many Removed Cousins You Have

Cousins are complicated, and figuring out how many removed cousins you have is no easier. It will depend on a number of factors including how many people in the generation before you had children, and so on. But, we can look at averages. 

On average, most people will have around 175 third cousins, and around 1570 fourth cousins. If you are of childbearing age, then  this means your children could have as many as 1570 fourth cousins. This means that you could have as many as 1570 third cousins once removed. 

Are They Really Relatives?

But, what you probably really want to know is if these people are actually close relatives of yours. Of course, this will depend on how close your entire family is, and it will almost always depend on your unique situation.

But, most of the time, people are not close to their third cousin once removed. Simply because of the additional generation between them. 

This isn’t true of everybody, and there are some families where everybody is close with their cousins. But, most of the time, people aren’t that close with their third cousins once removed.

However, this doesn’t mean that they aren’t family. Ultimately, it depends on your own, unique, family situation. 

Finding These Relatives

So, how do you find these relatives? Well, there are a couple of different ways that you can do this. These include using genealogy services, such as DNA testing, and family tree services to track your family line.

Both of these services are commercially available, and they are surprisingly affordable if you choose the right company. 

The easiest way to find these relatives is to do a DNA test through an ancestry company. You and your third cousins will share DNA, and most companies will be able to easily find relatives using this information.

In recent years, genealogy has become very popular, so there is a good chance that your close relatives will also be active on these websites. 

Who are your third cousins once removed? Find out with a DNA test!

DNA Testing

What-is-a-Third-Cousin-Once-Removed

If you decide to use DNA testing to find your third cousin once removed, then this is surprisingly easy. All you have to do is order a DNA testing kit from any reputable company.

We would recommend either using 23 and Me or Ancestry. Both of these companies also offer the ability to research your family tree, so it will make finding your cousins even easier. 

Once you have ordered your DNA kit, the process is really simple. All you need to do is follow the instructions in the kit, and deposit your DNA into the tube that is sent to you.

You can then send your sample off to the lab, and they will analyze it for you. This information will then be associated with your account, and you will be able to find your close relatives using these services.

Summary

In short, a third cousin once removed is the child of your third cousin. Likewise, you will be the third cousin once removed of your parent’s third cousin. Both you and your third cousin once removed will be related through your great-great grandparents. You can easily find your third cousins once removed using DNA testing services. Find out more in the guide above.

Who are your third cousins once removed? Find out with a DNA test!


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