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How to Tell a First Cousin from a Second Cousin

How to Tell a First Cousin From a Second Cousin You can find more How to Blogs at Most people can easily identify who their great-grandparents are. It isn’t incredibly difficult to figure out who your aunts and uncles are (and to sort out which are “blood relatives”). Cousins, however, can be more difficult to figure out. Here are some tips to help you tell a first cousin from a second cousin.

It might be just fine to introduce people as your “cousin” in a social situation. Many people will assume the person is your first cousin and will not feel a need to question further. It may also be convenient to round up all the “cousins” at a family reunion for group photo – without regard to exactly how each cousin is connected to the rest.

Genealogists, however, realize that “cousin” is often used as a general term. Genealogy is the study of family, so it makes sense for genealogists to take the time to figure out precisely how each individual is related to the rest. Is there a seasoned genealogist in your family? He or she will probably be very happy to help you sort out all your cousins.

What’s the different between a first cousin, a second cousin, and a third cousin? The numerical designation denotes the number of generations between two cousins and their nearest common ancestor. You, and your first cousins, share a grandparent.

Your first cousins are the children of your parent’s siblings. For example, let’s say your mother has a sister. That woman is your aunt. Your aunt is married to a man who is not a “blood relative” of yours. They have a child. That child is your first cousin. You, and this cousin, have the same grandparent. Your mother’s mother, and their mother’s mother, are the same person. Both you and your cousin identify that woman as “grandmother”.

You and your first cousin are from the same generation. Your parents, and your first cousin’s parents, are of the previous generation. The grandmother you share with your cousin is from the generation before that. There is one generation in between yours and your grandmother’s generation.

There are interesting things to note about first cousins. Your first cousins on your mother’s side of the family, and your first cousins on your father’s side of the family, are not each other’s first cousins. They don’t share any grandparents.

What’s a second cousin? A second cousin is a person that you share a great-grandparent with. To identify who your second cousins are, it is best to start with yourself. Figure out who your great-grandparents are. As you put together different branches of your family tree, you will uncover some people who have a great-grandparent that is the same individual as one of your great-grandparents. Those relatives are your second cousins.

Image by Erica Firment on Flickr.

Related Articles at

* Importance of Collateral Lines

* How Many Cousins Do You Really Have?

* Steps Along the Genealogy Path



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