Do you know how to determine cousin relationships? It’s easier than you may imagine. All you have to do is remember to count generations from the most recent set of cousins in your family tree that match up in the same generation and count the generations to you (or anyone else in your family tree). Here is how to do it.
You have probably heard people refer to such cousin relationships as “first cousin two times removed,” or “third cousin one time removed.” Do you know what they mean? As a beginning genealogist, figuring out cousin relationships can seem confusing at first, especially with all of those “removed” words and numbers coming up along with them. What do these words and numbers mean to you and your cousins? How can you even figure out what kind of cousin you are to someone? The good news is that there is an easy way to pull cousin relationships right out of your head on the spot if someone asks you.
The first thing to remember is that cousin relationships are all about generations. You are probably familiar with the easiest and best-known cousin relationship — the first cousin. A first cousin is simply the child of a brother or sister of one of your parents (so, a child of one of your aunts or uncles). A first cousin is in the same generation on the family tree as you. Your parents are one generation, the set of grandparents you share with your first cousins are another generation, and you and your first cousins are a generation. See? Easy.
Now, what if one of your first cousins has a child? What is that child to you? It is your first cousin once removed. This is because it is a child of your first cousin, but not of your same generation. It is one generation removed from you. It is in the next generation down the line on the family tree.
Who is a second cousin to you? That would be a child of one of your parents’ first cousins. Your parents and their first cousins are on the same generation as each other. You and the children of your parents’ first cousins are of the same generation as each other as well, but are second cousins, because you are of the generation after the first cousins. A child of your second cousin is a second cousin one time removed from you.
A good way to always figure out cousin relationships is to start with the most recent common grandparent or great-grandparent you and a person in your family tree share and count the generations from there. You can envision it as a pyramid in your head, with the most recent common ancestor at the top.
Say you want to know how your grandmother’s first cousin is related to you. Remember that your grandmother and her first cousin share grandparents. Those grandparents are your great-great-grandparents. Your great-great-grandparents are one generation, their children are another, but you start counting with your grandmother and her first cousin (as they are the first cousin generation to match up). Simply count down two generations, from your mom or dad to you. That makes your grandmother’s first cousin your first cousin two times removed.
When you know to count generations, you can quickly figure out any cousin relationship on your family tree.
Last revised 10/16/19