If you’re unfamiliar with what a second cousin is, the chances are you are not alone. However, our second cousins are closely related to us and if we do not know them all personally, we encourage you to find out a little more about them if you have the opportunity!
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Of course, some people might be familiar with all of their second cousins and some might have grown up with them in very close-knit families, however, for those who don’t know their extended family, you should know the chances are you have plenty of second cousins out there in the world.
This article tells you what a second cousin is and how they are related to you, as well as ways you can find your own. Let’s jump right in!
How Do Cousins Work?
Most of us know who our cousins are, or at least our first cousins. First cousins always share a common grandparent and since our grandparents are usually a big part of our lives, people often see their first cousins a lot more than their second or third.
However, when it comes to second, third, fourth cousins, the cousin label simply changes depending on which grandparent the cousin has as their common ancestor.

Are you sure you know who all your second cousins are? Find out by taking a DNA test!
What Are Second Cousins?
Second cousins are people in your family who share great-grandparents. They are descended from different offspring of those great-grandparents and to put it in simpler terms, the grandparents of second cousins are siblings.
You can also understand second cousins by looking at your first cousins. This is a relationship most people are familiar with and to work them out this way, the children of first cousins are second cousins.
First cousins share a grandparent as their common ancestor. The children of first cousins will then share great-grandparents as their common ancestors, making them second cousins.
If your first cousin has children, and you have children, all of these children will be second cousins to each other. You are also a second cousin to the children of your parents’ first cousins.
We know this seems confusing but as long as you keep in mind the common ancestor is the great-grandparents, this should help you work out who your second cousins are.
Are Second Cousins Part Of The Family?
Of course! Second cousins are considered to be a part of the family and are not even considered distant family.
Despite them being ‘family’, it is still legal in every US state to marry your second cousin. However, since they are part of the family, they only make up 0.2% of marriages in the US.
Are They Blood-Related?
Yes, second cousins are part of the family and they are blood-related. You share DNA with all of your second cousins, and on average you share 3.13% of DNA, or this equals 233 centimorgans.
Whilst this does not seem a lot, it is a substantial amount considering first cousins only share around 7.5% DNA.
Second Cousins Removed
What are second cousins removed? Well, if you and your second cousin are not in the same generation, then you are more than likely, second cousins removed. The child of any second cousin becomes a second cousin-once-removed.
For instance, you are the second cousin once-removed to the second cousins of your mother. In this case, the common ancestor is the great-great-grandparents.
This still means you are second cousins, however, just that there is one generation between you both.
The person closest to the common ancestor determines the type of cousin relationship, whether this is first, second or third. To work out how ‘removed’ they are, you simply need to calculate the number of generations between them.
You can have second cousins that are three, four, five, six, or seven times removed, and much more and you will usually find second cousins many times removes when doing any genealogy research to find relatives of distant ancestors.
Are you sure you know who all your second cousins are? Find out by taking a DNA test!
Determining Your Second Cousin
If you are trying to determine who your second cousin is, think of a relative first who might be your second cousin and who you might share a common ancestor with.
This is the first thing you need to determine. You then need to figure out who is closest to the common ancestor in the number of generations between you.
The common ancestor must at least be a great-grandparent to one of you and if they are the common ancestor to both of you, you are second cousins once-removed.

How Many Second Cousins Do I Have?
On average, most people can have around 28! However, some people will have less than this and some people might even have many more.
This number will vary from family to family and factors that determine how many second cousins we have include the number of children the great-grandparents had, how many of those survived to adulthood and had children, and how many children those children produces.
How Can I Find My Second Cousin?
If you are on the hunt to discover and learn more about who your second cousins are, people often choose one of three ways.
Each way means you will need to actively use your research skills, but we promise in the process, you’ll have a lot of fun and learn a lot more about your family.
Option One: Using Your Parents
This is the simplest and most common way of finding out who your second cousins are. Most parents can easily tell us the first names of their first cousins, or at least who their aunts and uncles are.
Once you have found out these names, you are much nearer to finding out who your second cousins are already! All you need to do is simply contact your first cousins, and explain that you are doing some digging into the family tree.
You might find they are interested in finding out more about you and the family too!
Option Two: Building Your Family Tree
This brings us on to our next point, if you know who your great-grandparents are, you can easily locate your second cousins by beginning to build your family tree.
To do this, start by researching each of your great-grandparents’ children, and their descendants. By using this method, it should take you no time at all to arrive at your second cousin’s in a few generations.
Option Three: Taking A DNA Test
Taking a DNA test is sometimes the most complicated route of finding your second cousins, but if you opt for this method, companies such as 23and Me and Ancestry DNA can help you find your second cousins by offering you a DNA test.
Your cousins share DNA, as we mentioned previously in this article and this means if any of your second cousins have also taken a DNA test with the same company, they will show up on your DNA match list as genetic relatives.
Are you sure you know who all your second cousins are? Find out by taking a DNA test!
Final Thoughts
We hope by reading this article you now understand what a second cousin is and how they are part of your family!
If you have been brought up in a very close-knit family, you will often find you already know your second cousins and they’re at every family gathering.
However, if this is not the case and this is something you would be interested in, get digging! Ask your parents, start figuring out your family tree, and get to know those second cousins!
Use these genealogy forms to stay organized as you discover your family history!