There is often a problem deciding on family relationships in genealogy, if you are reading this page then you have access to a computer and most likely have the use of a Genealogy Program - most of which have their own relationship calculator. That's ok, it tells you the relationship, but rarely tells how it is worked out or gives an understanding of the underlying reasoning.

We all know about direct descent - son/dau - grandson/dau - etc, it's the distant cousins that cause the problem. Because we all know the first 2 generations - we need not bother to work them out, but let's use that number 2 as a basis for a calculation:
To find the relationship between two descendants who are say,
generation 7 and generation 4 from their last common progenitor:

Subtract our basis number 2 (as above) from the lower of the two generation numbers,
4 minus 2 = 2
This means they are second (2) cousins

Subtract the lower generation number from the higher one
7 minus 4 = 3
This means they are 3 times removed. easy!



The chart below may help to show the family relationship between two people.
Find the relationship to the common progenitor (ancestor) of the first person going down the edge of the chart, now find the relationship to the same common progenitor (ancestor) of the second person across the top row of the chart.
The box where the row & column intersect shows the relationship between these two people.

1
2
3
4
5
6
7
8
9
10
1
Common
Progenitor /
Ancestor
Son or Daughter
Grandson or Daughter
Great Grandson or Daughter
2nd Great Grandson or Daughter
3rd Great Grandson or Daughter
4th Great Grandson or Daughter
5th Great Grandson or Daughter
6th Great Grandson or Daughter
7th Great Grandson or Daughter
2
Son or Daughter
Brother or Sister
Nephew or Niece
Grand Nephew or Niece
Great Grand Nephew or Niece
2nd Great Grand Nephew or Niece
3rd Great Grand Nephew or Niece
4th Great Grand Nephew or Niece
5th Great Grand Nephew or Niece
6th Great Grand Nephew or Niece
3
Grandson or Daughter
Nephew or Niece
First Cousin
First Cousin Once Removed
First Cousin Twice Removed
First Cousin Three Times Removed
First Cousin Four Times Removed
First Cousin Five Times Removed
First Cousin Six Times Removed
First Cousin Seven Times Removed
4
Great Grandson or Daughter
Grand Nephew or Niece
First Cousin Once Removed
Second Cousin
Second Cousin Once Removed
Second Cousin Twice Removed
Second Cousin Three Times Removed
Second Cousin Four Times Removed
Second Cousin Five Times Removed
Second Cousin Six Times Removed
5
2nd Great Grandson or Daughter
Great Grand Nephew or Niece
First Cousin Twice Removed
Second Cousin Once Removed
Third Cousin
Third Cousin Once Removed
Third Cousin Twice Removed
Third Cousin Three Times Removed
Third Cousin Four Times Removed
Second Cousin Five Times Removed
6
3rd Great Grandson or Daughter
2nd Great Grand Nephew or Niece
First Cousin Three Times Removed
Second Cousin Twice Removed
Third Cousin Once Removed
Fourth Cousin
Fourth Cousin Once Removed
Fourth Cousin Twice Removed
Fourth Cousin Three Times Removed
Fourth Cousin Four Times Removed
7
4th Great Grandson or Daughter
3rd Great Grand Nephew or Niece
First Cousin Four Times Removed
Second Cousin Three Times Removed
Third Cousin Twice Removed
Fourth Cousin Once Removed
Fifth Cousin
Fifth Cousin Once Removed
Fifth Cousin Twice Removed
Fifth Cousin Three Times Removed
8
5th Great Grandson or Daughter
4th Great Grand Nephew or Niece
First Cousin Five Times Removed
Second Cousin Four Times Removed
Third Cousin Three Times Removed
Fourth Cousin Twice Removed
Fifth Cousin Once Removed
Sixth Cousin
Sixth Cousin Once Removed
Sixth Cousin Twice Removed
9
6th Great Grandson or Daughter
5th Great Grand Nephew or Niece
First Cousin Six Times Removed
Second Cousin Five Times Removed
Third Cousin Four Times Removed
Fourth Cousin Three Times Removed
Fifth Cousin Twice Removed
Sixth Cousin Once Removed
Seventh Cousin
Seventh Cousin Once Removed
10
7th Great Grandson or Daughter
6th Great Grand Nephew or Niece
First Cousin Seven Times Removed
Second Cousin Six Times Removed
Third Cousin Five Times Removed
Fourth Cousin Four Times Removed
Fifth Cousin Three Times Removed
Sixth Cousin Twice Removed
Seventh Cousin Once Removed
Eighth Cousin

The numbers and wording used to denote how many "greats" to attach to an individual are displayed in many different ways, none are right or wrong, it is just personal choice,  
Great Great Great    -  3rd Great  -   3 times Great   -   3xGreat   -   Great3   -   GGGreat   -   GGG    
are all used throughout the english speaking world.


More Cousin Terminology: You may also come across these terms used to describe cousins.

* double first cousins are when a set of brothers marries a set of sisters, or a brother and a sister marry another sister and brother, and they produce children. These children end up sharing all lineal and collateral relatives. (double first cousins share a quarter of their genetic material [25% consanguinity] and in many cultures & religions there is a taboo, an objection to them marrying or procreating)
* A parallel cousin, sometimes also called an ortho-cousin, is the child of your mother's sister or your father's brother.

* A cross-cousin is the child of your mother's brother or of your father's sister.
* A cousin couple is two cousins in a marriage or sexual relationship.

 

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