What Is "Second Cousin Once Removed?"

A term often found in genealogy is "removed," specifically when referring to family relationships. Indeed, almost everyone has heard of a "second cousin once removed," but many people cannot explain that relationship. Of course, a person might be more than once removed, as in third cousin, four times removed.

In short, the definition of cousins is two people who share a common ancestor. Here are a few definitions of cousin relationships:

First Cousin: Your first cousins are the people in your family who have at least one of the same grandparents as you. In other words, they are the children of your aunts and uncles.

Second Cousin: Your second cousins are the people in your family who share the same great-grandparent with you.

Third, Fourth, and Fifth Cousins: Your third cousins share at least one great-great-grandparent, fourth cousins share a great-great-great-grandparent, and so on.

Removed: When the word "removed" is used to describe a relationship, it indicates that the two people are from different generations. "Once removed" indicates a difference of one generation, "twice removed" indicates a difference of two generations, and so forth.

For example, the child of your first cousin is your first cousin, once removed. That is, your cousin's child would be "almost" your first cousin, except that he or she is one generation removed from that relationship. Likewise, the grandchild of your first cousin is your first cousin, twice removed (two generations removed from being a first cousin).

Many people confuse the term "first cousin, once removed" with "second cousin." The two are not the same.

Keep in mind that you and a relative only need to share one grandparent to be first cousins, or share one great-grandparent to be second cousins, etc. If the ancestor in question had more than one spouse and the two of you are descended from different spouses, you are full cousins. There is no such thing as a "half cousin" although you will hear people use that term occasionally.

The following consanguinity chart may help to explain the relationships:

Cousins Table

A cousin is someone who shares a common ancestor with you. Use this chart to determine your relationship.

                                                                                                                                                                       

Find your     ancestor here →     Find your cousin's ancestor here ↓	Grand-     parents	G-     Grand-     parents	GG-     Grand-     parents	GGG-     Grand-     parents	GGGG-     Grand-     parents
Grand-     parents	1st cousins	1st cousins     1x removed	1st cousins     2x removed	1st cousins     3x removed	1st cousins     4x removed
G-     Grand-     parents	1st cousins     1x removed	2nd cousins	2nd cousins     1x removed	2nd cousins     2x removed	2nd cousins     3x removed
GG-     Grand-     parents	1st cousins     2x removed	2nd cousins     1x removed	3rd cousins	3rd cousins     1x removed	3rd cousins     2x removed
GGG-     Grand-     parents	1st cousins     3x removed	2nd cousins     2x removed	3rd cousins     1x removed	4th cousins	4th cousins     1x removed
GGGG-     Grand-     parents	1st cousins     4x removed	2nd cousins     3x removed	3rd cousins     2x removed	4th cousins     1x removed	5th cousins

For instance, we will assume that you and your newly-found relative are both descended from John Smith. This common ancestor is your great-grandfather and also is the great-great-grandfather of your newly-discovered cousin.

In the above chart, go across the top to find your ancestor: great-grandfather.
Next, go down the left column to find your cousin's relationship to the same person: great-great-grandfather.

Now notice where the two intersect in the above chart: you and your new cousin are actually second cousins, once removed.

You may prefer to use an automated online tool to determine relationships. Ancestor Search has one that I found simple to use. Take a look at http://www.searchforancestors.com/utility/cousincalculator.html

Here are a few other terms you may encounter when determining relationships:

HALF - Means you share only one parent. Example: half-brothers may have the same father but different mothers, etc.

STEP - Not blood kin, but a close legal relationship due to re-marriage of a parent, such as step-mother, step-brother, step-son, etc.

DOUBLE FIRST COUSINS - Are first cousins twice, once on your father's side and once on your mother's side, since your father's sibling married your mother's sibling.

IN-LAW - They are not really blood kin but are treated as such because they married blood kin.

Example: Your mother-in-law is not really your mother but is treated as such because you married her daughter/son. In law, you and your spouse are considered "one". Also your brother-in-law is your brother because your parents are also his parents, in "law" (mother-in-law, father-in-law, etc.).

KITH and KIN - "Kith" are friends and acquaintances whereas "Kin" are blood relatives or someone treated as such, in law.

By the way, it is estimated that everyone has approximately 4 trillion 20th cousins! In other words, everyone is related to nearly everyone else.

Comments

[Steve]

One of my favorite features of Legacy Family Tree is the Relationship Calculator where it figures out the relationship like this with 2 people. You end up with things like "Husband of 2nd cousin, once removed" :) Or, "wife of great grand uncle"

[Adward]

Relationship calculators are great! That one in Personal Ancestral File saves me a lot of time.

[Mark Tucker]

Check out the interactive Kinship Calculator just posted to the ThinkGenealogy blog:

http://www.thinkgenealogy.com/2009/07/25/interactive-kinship-calculator/

[Sam Brainerd]

The son of my first cousin is my first cousin once removed, just as I am his first cousin once removed. The identical phrases fail to reveal me as the older and him as the younger, which is one reason why the terminology is opaque to most people.

I think a better phrase would be for me to call him my "cousin-nephew" and for him to call me his "cousin-uncle." After all, I am much more like an uncle to him than I am a cousin. And he is like a nephew to me, only a little more distant.

Variations on this theme would serve well as names for near relatives who actually know one another. Second cousins would be "cousin-cousins." For more distant relations, who rarely know each other in this scattered culture, the standard third- or fourth-cousin terms would do fine. But for closer relations we need something less technical and more familiar.

[boeufdaisy]

Sam, there are standard phrases that distinguish that relationship (the son of your first cousin and you).

He is your first cousin once removed in the descendancy; you are his first cousin once removed in the ascendancy.

Not that that would clarify it for most people....

[Steve Spicer]

When I have to explain it to someone I ask them to think of their first cousin. Then ask them what their relationship is to their first cousin's child. First cousin once removed. They get it then.
What there isn't a term for is my wife and my relationship to my daughter-in-law's parents, with whom we are good friends. "Parents-in-law"? Naw...that's not right. That's my son's relationship to them. Any suggestions?

[Jim Bartlett]

From your explanation, which I accept, the chart should not have the "s" after "grandparent"

[Dick Doherty]

At times we find that the parties to a marriage have some blood relationship. These marriage records (usually church records) often show that there was a "Dispensation" made for this marriage due to a certain degree of consanguinity - 2nd degree, 3rd degree, etc. Has anyone seen a chart similar to the above one that represents these types of blood relationships?

[David]

Steve Morse has a very useful "relationship calculator." Just look for that phrase under the heading of "Births, deaths and other vital records" at stevemorse.org

[Peter Calver]

Here's how to work out the relationship between cousins without any tables:

(a) figure out who the most recent common ancestor is;
(b) count how many generations back that ancestor is in your tree;
(c) count how many generations back that ancestor is in your cousin's tree
(d) take the lower of the two numbers and subtract 1; if the answer is n then you are nth cousins
(e) take the difference between the two numbers; if the answer is m, then you are nth cousins m times removed

As for half-cousins, this may not be an 'official' term, but I think it's a very useful way to describe a cousin who shares one ancestor not two (at least until someone comes up with a better term).

[Shon R. Edwards]

I have second double cousins. My grandfather and grandmother were respectively brother and sister to their grandfather and grandmother.

[Margaret Tyrrell]

Family Tree Maker also provides a kinship file. I have no problem determining the direct relationships. But I find the term grand being used in another way i.e. great grand uncle. Some further explanation on the use of "grand" in this way, apparently for sibling relationships(?), would be helpful.

[Jay Fonkert]

Interesting this should appear today. WCCO-TV in Minneapolis-St. Paul dealth with this question in its 24 July newscast. They do a daily "Good Question" feature, and Friday's viewer question had to do about defintions of 2nd and 3rd cousins. They came to me for the answer. The video is posted at:

http://wcco.com/goodquestion

I don't know how long it will be posted on the station's website.

[John Bennison]

Thanks for the helpful clarification.

When speaking of double cousins, cousins by marriage, and family dispensations, things can get very complex. For those who think they understand all this, here's a link to the lyrics of an old folk song, "I am my own Grandpa" - http://gean.wwco.com/grandpa/

The link includes a sketchy descendant diagram illustrating the relationships and shows how with blurring the distinction between blood and marriage relatives, it really is possible to be one's own grandparent. Or at least to get a clever song out of it.

Enjoy.

[Jami Davis]

I call my sister-in-law's sister my sister-in-law once removed, as a joke, but it is wordy to explain the relationship with endless possessives (my brother's wife's sister, etc). In our smallish families, where we tend to include "everyone" at holidays and family occasions, we do need a good word for the in-law's other family members.

[Alice McCabe]

In the South of U.S., people call everyone "cousin". But if they say "Cousin Betty", that means Betty is OLD.Don't ask me why!
Alice

[Evelyn Hendricks]

In the south we call our older cousins "Cousin" as a title of respect for older people. For example, my mother's niece was six months younger than my mother. I would never have called my mother by her given name, nor would I have called my cousin by her given name without some title of respect for her age. We also called our parents friends "Aunt or Uncle" given name out of respect. I kind of miss the formality of my generation. I am now in my eighties and will probably never live to see more formal manners.
Evelyn

[Steven Frome]

Steve Spicer wrote (July 27, 2009 at 06:33 AM):

What there isn't a term for is my wife and my relationship to my daughter-in-law's parents, with whom we are good friends. "Parents-in-law"? Naw...that's not right. That's my son's relationship to them. Any suggestions?

Response: There is no word in English for this. The word in Yiddish is: machatoonum. This word describes your child's in-laws.

[Tony Zeppetella]

These terms are almost all imprecise, which drives me, as a mathematician, crazy. To complicate matters, they are also often used sloppily. Sometimes any non-sibling relative of the same generation is simply called "cousin." Any non-parental relative of the next higher generation is called "aunt" or "uncle." This does very little to tell us family historians what the relationship is. I have relatives that my parents called cousins that took me years to find their actual spot on the family tree! One of these is still uncertain. Genealogists should encourage more precision in the terminology.

[Nancy Allen]

I thought first cousins were the children of your parents siblings. not your grandparents. So what do you call the children of your parents brothers and sisters? Just cousins.

[Penny Hayes]

Our Uncle Bill was on friendly terms with his ex-wife's current husband. With tongue firmly in cheek, Uncle Bill often described him as his "husband-in-law". :)

[Elaine Mayfield]

I like to use a 'grocery list' format for cousin relationships: Place the common ancestor at the top; under him/her place their two children side by side; then list the succeeding names on down. The top two people are brother/sister; the next are first cousins, the next second cousins, etc. all the way down. Then it is easy to add the 'removes' - or 'generations' as you wish.

Steve, we call our children's in-laws 'Co-Inlaws'!

[Adrian B]

"I find the term grand being used in another way i.e. great grand uncle. Some further explanation on the use of "grand" in this way, apparently for sibling relationships(?), would be helpful."

There is confusion on this point... (no surprise there then!)

Aunts and uncles are siblings of parents.
Usually...
Great-aunts and Great-uncles are siblings of grandparents.
Great-great-aunts and Great-great-uncles are siblings of great-grandparents.

Sometimes...
Grand-aunts and Grand-uncles are siblings of grandparents.
Great-grand-aunts and Great-grand-uncles are siblings of great-grandparents.

In the "usual" scheme, there are different numbers of "greats" between the terms for the aunts, uncles and 'parents on the same generation BUT the total number of Gs stays the same (i.e. total number of greats plus number of grands)

The "sometimes" scheme is more logical in that the number of greats and grands individually match across the same generation. However, grandaunt and granduncle seems rare to me - it crops up more in my Scots relatives but doesn't appear to be exclusively Scots.

Just to really foul things up - I have seen someone claiming that grandaunt on one generation should be followed not by great-grandaunt on the next but simply by great-aunt.

Reader beware! (I note I also can't decide myself whether to hyphenate or not!)

[Brenda Wordsworth]

Different cultures have different concepts of family/whanau and the relationships that are important such as in the Maori of new Zealand. See the last two paragraphs of this article published in the Dominion Post July 29 2009, by Janet Holmes writing the Watch Your Language column. http://www.stuff.co.nz/opinion/2700272/Losing-a-language-puckeroos-your-perspective
Maori and many other New Zealanders nowadays use the word "cuzziebro" to described any member of the family/whanau.

[Mariann]

Reading these comments reminds me of the old song "I'm my own grandpa". Now my question is: what do you call the relationship between my great grand-daughter and my first cousin's daughter? These two girls are the same age and play together but what are they to each other?

[Dick Eastman]

---> what do you call the relationship between my great grand-daughter and my first cousin's daughter?

Second cousins twice removed

0 Common ancestor
/ \
0 0 Siblings
| |
0 0 First cousins (with you on the left)
| |
0 0 Second cousins (your daughter is on the left
| and your first cousin's daughter is on the right)
|
0 Second cousins once removed (your grandchild)
|
0 Second cousins twice removed (your great-granddaughter)

[Mariann]

Thanks Dick, your diagram really helped. I've used the "ladder" system as someone else described but always wondered if I was doing it right and your illustration helped. Thanks again.

[Dominique]

What are the complications if second cousins hook up, madly in love, want to be together. This is on the mothers side of the family tree. I heard that if it was on the fathers side there would be a problem, but because its on the mothers side, its okay. Is this correct? Would it be okay for them to see and be with each other? How will this affect their children.

[Cindi]

Mariann, your great grand-daughter and your cousin's daughter would be 2nd cousins twice removed.