Family Relationship Chart: Terms And Classifications of Cousins


Well, we may not be related; but have you ever wondered about your cousins and their exact relationship to you? Some may be first cousins. That’s simple. If your parent’s brother or sister has kids, they are your first cousins. But what if your first cousins have kids? What are they referred as?

Or how about this one: What is your relationship to your grandfather’s brother’s son?

Some time ago we had a big fat Greek reunion (yes I am half Greek). And there were tons of relatives! I was trying to figure out if people were second or third cousins, or first once removed. Anyway, it inspired me to look up the information and study it more. There are plenty of charts online, but I made my own. And I will explain how it works.

The Relationship Chart

To find out the relationship between you and another relative first go to the common ancestor box and plug in your closest generation grandparent that you and that relative have in common. For instance Grampa Harry may be your grandfather, but a relative’s great grandfather. If this is the case, than that relative is your first cousin once removed.

Try it with all your relatives, even those you know the relationship between (except your own parents or siblings)
I’ll start. My Aunt Helen is my dad’s sister. I can plug in my grandmother (Yia Yia) in the common ancestor box.. I move down the left column to find me (grandchild). I move across the top to find Aunt Helen’s relationship to my grandmother, which is child. Moving down and across from the two spots they meet at the box nephew or niece. So I am Aunt Helen’s niece.

So if my cousin Vinny is my first cousin and he has a grandchild how am I related to his grandchild?
His grandchild and I have my grandparents as a common ancestor. So down the left column I stop at grandchild for me. Across the top I need to go all the way to great great grandchild. So cousin Vinny’s grandchild is my first cousin twice removed.

Relationship Terms

First Cousins – These are people you share the same set of grandparents with. Basically they are the children of your Aunts and Uncles (not great aunts or uncles).

2nd Cousins– These people have the same great grandparents as you, but not the same grandparents. So my grandfather’s brother’s grandchild would be my 2nd cousin.

3rd, 4th, etc Cousins– Third cousins share the same great great grandparents. Fourth cousins share the same great great great grandparents, etc.

The Term Removed– This means a person is a generation away from what your generation is. In other words my first cousin and I are in the same generation, we share the same grandparents. My first cousin’s child is in a different generation then I am, my grandparents are their great grandparents. So we are first cousins (the relationship I have with my first cousin) once removed (because they are one generation away from me). So my first cousin’s grandchild is my first cousin twice removed.

Now Quiz Yourself

See how well you can figure out these relationships

Simple Flow Chart

………./.. \
………/…. \
…….B …..C
……./ ………\
……/ ………..\
….D …………E
…./……………. \
…/……………… \
F………………… G

So A is B&C’s parent
A is D&E’s grandparent
A is F&G’s great grandparent

To find the relationship between B&G simply go to the chart. B is a child to A. So find child across the top. G is a great grandchild to A, so find great grandchild down the side. Therefore G is a Grand-nephew or niece to B.

Other Interesting Classifications of Cousins

Double first cousins– When two siblings marry two other sibling. (so if Bob and Joe are brothers and they marry sisters Jane and Josie. Or Mike and Jill who are brother and sister marry Faith and Jack who are also brother and sister). The children of these couples are related to each other through both parents’ families. Double first cousins have both sets of grandparents in common. Genetically, they are as related as half-siblings.

“identical” twins If identical twins marry another set of siblings the kids of the couples are more related than half-siblings but less related than full siblings (they are genetically equivalent to 3/4 siblings) although they are legally double first cousins. If identical twins marry another set of identical twins (sometimes called “quaternary marriage”), genetically they are like full siblings. They are classified as double first cousins.

There are even other types of cousins.
Click Here to Check it out