If you’re doing family genealogy, you might have heard the terms “once removed,” “twice removed,” and so on. These indicate the number of generations you are separated from a particular cousin. For example, a first cousin once removed is someone whose parents are the siblings of your parent or grandparent. Their children are also your first cousins once removed.
Origins
When discussing your family tree, you often hear terms like “1st cousin once removed” and other degrees of kinship. But what do they mean? Knowing these relationships is essential because they can help you learn more about your ancestors and where you came from.
First cousins are people that share a parent with you or your siblings. They are also blood relatives but aren’t necessarily close in age to you or your children. First cousins share a common ancestor within the last four generations. The “once removed” part of this relationship refers to the number of generations between your cousin and the common ancestor. The closer to your ancestor, the less “once removed” you are. For example, your aunt’s child is your first cousin once removed because they are two generations younger than you.
You can calculate this by adding the number of generations between you and your cousin, then dividing that number by 4. If you and your first cousin have the same grandparents, you are both 1st cousins once removed. But if you and your first cousin have different grandparents, you are both 2nd cousins once removed. The further away from your common ancestor, the more “removed” you are. For example, your grandmother’s great-grandchild is your first cousin twice removed because it’s two generations away from you.
Meaning
Getting the terms cousins and degrees of cousin-ness straight can be confusing when researching family trees. You might see relatives referred to as first cousins once removed, second cousins twice removed, or even third cousins four times removed. So what does each of these mean?
A first cousin once removed is a person with whom you share a common ancestor who is also your grandparent. You are directly related to your first cousins, meaning you share a parent or a grandparent with them. A second cousin once removed is the child of your first cousin or the child of their parent. You and your second cousin share a great-grandparent.
The “removed” part of the relation refers to how many generations separate you from your cousin. The number of ages between you and your cousin determines the degree of your relationship.
For example, suppose your grandmother’s cousin’s daughter has three generations between them and you. In that case, they are your second cousin once removed because three generations are between you and their shared common ancestor (your grandparents). However, suppose your grandmother’s niece only has two generations between her and you. In that case, she is your first cousin once removed because there are only two generations between you and her shared ancestor. This is known as the shortest distance rule.
Significance
Whether you’re calculating cousin relationships for DNA purposes or to understand your family tree, knowing the significance of “once removed” is essential. The number of generations that separate you and your cousin determines how close a relationship you have. Generally, if you share a common ancestor, you are considered first cousins; the more generations separate you, the more distant the relationship becomes.
The meaning of “once removed” is pretty simple. You’re a first cousin once removed if the child of your first cousin is one generation above you. If your first cousin’s child is two generations above you, you are a second cousin once removed.
If you’re unsure which generation your cousin is in, count how many “greats” are in their title and add one. For example, if your aunt’s cousin is the grandson of your uncle’s brother, you are her first cousin once removed because 1 + 2 = 3.
If someone is a first cousin once removed from you, they share about 6.25% of their DNA, according to Genetic Genealogy Wiki. This is less than half of what you would expect to share with your closest cousin, and it gets even smaller as the number of generations increases. This is because fewer genes are passed down with each generation. For this reason, it’s common for DNA matches to be a first cousin once removed.
Examples
When someone is described as a first cousin once removed, it means there is one generation between you and them. This can be either a generation above you or below you. For example, if your mom’s or dad’s cousin has children, those kids are your first cousins once removed.
The term can also be applied to the grandchildren of your first cousins, making them your second cousins once removed. However, this is a less common use of the term. It is more common to refer to the grandchildren of your first cousins as your nieces or nephews.
In genealogy, it is often necessary to break down the relationships of your ancestors into different categories to better understand them. This is because the number of generations between you and your cousin can make a difference in how close or distant a relationship is. This is why there are terms such as once removed, twice removed, etc.
It cannot be obvious when determining how many generations you are from your cousins, mainly when they are described as once removed, twice removed, or even thrice removed. Fortunately, there is a simple way to keep track of this. The key is to remember that the number of generations between you and your cousin makes them once, twice, or thrice removed.
