What is a Fifth Cousin?

Marc McDermott
February 22, 2022

Want to discover everything there is to know about fifth cousins? Then you’ve come to the right place. The bigger the family tree, the more tricky it is to tell how we are related to other people, and whether fifth cousins are blood relations.

We’re going to answer all the burning questions about this interesting side of your family tree, so you can understand it better.

How is a Fifth Cousin Related to Me?

A fifth cousin is a relative who shares a set of great-great-great-great-grandparents with you. To put it simply, a fifth cousin is a sibling of your great-great-great-grandparents. The number of cousins is a way of telling how many generations you both are from your common ancestor.

This basically means that second cousins share a great-grandparent, third cousins share a great-great-grandparent. Subsequently, fifth cousins share a great-great-great-great grandparent, marking what is the 6th generation in your family tree. 

Created with my cousin calculator tool.

Are Fifth Cousins Considered Family?

Fifth cousins are considered distant cousins. Because of the number of fifth cousins, the large degree of separations between cousins removed by six generations means many do not consider them as a family in the same way they do second or third cousins. 

Respectively, second and third cousins are related at six and eight degrees of separation, making fifth cousins, who are separated by twelve degrees, a far more distant relation. 

But why are they considered distant cousins? This is because we have so many of them. Figuring out how many you have can be tricky, but is easy when you know how.

The degree of separation method is used to measure the relationship between fifth cousins. Those who are from the same great-great-great-great-grandparent have twelve degrees of separation. 

This “twelve degrees” is worked out by counting six generations up to a fifth cousin with the same common ancestor, the fourth great-grandparent, and subsequently combining this with the six generations from the other fifth cousin. 

Are Fifth Cousins Blood-Related?

Fifth cousins are related, but there is a chance they do not share DNA. In fact, there is only a 10-15% chance of sharing genetics with any fifth cousin. 

Even if you and our fifth cousin are related by blood, the DNA shared will be small, especially when compared to closer cousins. It is unlikely that you share identical DNA with your fifth cousin. You may be genetically related to each of your fifth cousins, but it is possible to not share DNA with any of them. 

What grandparents do fifth cousins share?

With at least one common ancestor, fifth cousins share at least one of their great-great-great-great-grandparents, but they are the descendants of the different children from this ancestor. 

Fifth cousins do not share the same grandparents, this honor belongs to first cousins

How many fifth cousins do I have?

You may want to think twice about inviting all your fifth cousins to your wedding since the average person has over 17,000. You’d need to rent a stadium to fit them all in. 

The exciting thing about exploring your family tree is discovering the sheer numbers involved in your wider family. Everyone has a unique story and is all part of the massive family story that makes up your rich history. All fifth cousins are descendants of your great-great-great-grandparents, and they would have lived in a world that was incredibly different from the world you live in today. 

The next time you examine your family tree, try and consider the journey each member has been on, it’ll blow your mind!

What Does Fifth Cousin Once Removed Mean?

The child of your fifth cousin or the fifth cousin of your parent is known as a fifth cousin once removed. Two cousins that share a common ancestor but are not the same number of generations from great-grandparents are said to be “removed.”

Only cousins that are not removed are part of the same generation. Essentially, this means a first cousin is the child of your parent’s brother or sister. Your parents and their siblings are part of the same generation, in the same way, that you and their siblings’ children are.

No matter which cousin is in question, any cousin that is once removed is concerned one generation or above the other. 

Therefore, your parents’ first cousins are your first cousins, but they are once removed because of the generation between you. 

If your fifth cousin has a child, then this child would be once removed from you because you are a generation above them. 

For fifth cousins, the most recent common ancestor once removed is the great-great-great-grandparent of a fifth cousin, and the parent of the fifth cousin once removed.  

What Does Fifth Cousin Twice Removed Mean?

For any relationship to be “removed” the cousins in question cannot share a generation in common. A fifth cousin that is twice removed is a cousin that is two generations away from another, either younger or older. 

When cousins are not removed, it means they are part of your grandparents twice removed. This means your cousin will either be in your grandparent’s generation or the same generation as your grandchildren, as each is removed by two generations. 

What Is a Half-fifth Cousin?

Everyone has lots of half cousins, and can be determined as half-first, half-third, half-fourth, half-fifth, and even half-sixth cousins. 

Multiple situations lead to two relations being half cousins. Generally speaking, half cousins share approximately half the DNA found in full cousins. We all have 32 sets of great-great-great-great-grandparents and those who share one set are fifth cousins. 

If two people only have one person in common that is a great-great-great-great-grandparent, then they are known as half-fifth cousins. 

Half cousins generally occur when one member of the family remarries and has children with another person. One grandparent can have offspring with two different people, making the offspring half-siblings, and half cousins. 

Read more about cousinhood.

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