Cousin

For other uses, see Cousin (disambiguation).

"Cousins" redirects here. For other uses, see Cousins (disambiguation).

A cousin is a relative with whom a person shares one or more common ancestors. In the general sense, cousins are two or more generations away from any common ancestor, thus distinguishing a cousin from an ancestor, descendant, sibling, aunt, uncle, niece, or nephew. However in common parlance "cousins" typically refers to "first cousins", individuals who share a grandparent.

Systems of "degrees" and "removals" are used in the English-speaking world to describe the exact relationship between two cousins (in the broad sense) and the ancestor they have in common. Various governmental entities have established systems for legal use that can precisely specify kinships with common ancestors existing any number of generations in the past, though common usage often eliminates the degrees and removals and refers to people with common ancestry as simply "distant cousins" or "relatives".

Basic definitions

"First cousin once removed" redirects here. For the documentary film, see First Cousin Once Removed.

The ordinals in the terms "first cousins", "second cousins", "third cousins", refer to the number of generations to one's closest common ancestor. The number of "G" words used to describe this ancestor will determine how close the relationship is. For example, having "great-great-grandparents" in common would be third cousins.

When the cousins are not the same generation, they are described as "removed". In this case, the smaller number of generations to the common ancestor is used to determine the degree, and the difference in generations determines the number of times removed. Note that the ages of the cousins are irrelevant to the definition of the cousin relationship.

Term	Definition	Latest Common Ancestor	Example	Chart
First cousins	A person shares a first cousin or cousin relationship with the children of their parents siblings.	Cousins share least one set of grandparents.	Joseph and Julie	Jason Beatrice James Helen Eugene Mary Nancy Joseph Julie Roger Gordon Laura Christina Matt Sam Lyla
Second cousins	A person shares a second cousin relationship with the children of their parents cousins.	Second cousins share at least one set of great-grandparents.	Gordon and Matt
Third cousins	A person shares a third cousin relationship with the children of their parents second cousins.	Third cousins share at least one set of great-great-grandparents.	Sam and Lyla
First cousins once removed	A person shares a first cousins once removed relationship with their parents cousins and their cousins children.	At least one set of one person's grandparents are the great-grandparents of the other person.	Gordon and Julie, Joseph and Matt
First cousins twice removed	A person shares a first cousins twice removed relationship with their grandparents cousins and their cousins grandchildren.	At least one set of one person's grandparents are the great-great-great-grandparents of the other person.	Sam and Julie, Joseph and Lyla
Second cousins once removed	A person shares a second cousin once removed relationship with their parents second cousins and their second cousins children.	At least one set of one person's great-grandparents are the great-great-grandparents of the other person.	Sam and Matt, Gordon and Lyla

Relationship charts

Cousin chart

A "cousin chart", or "table of consanguinity", is helpful in identifying the degree of cousin relationship between two people using their most recent common ancestor as the reference point. Cousinship between two people can be specifically described in degrees and removals by determining how close, generationally, the common ancestor is to each person.

If your →		Parent	Grandparent	Great-grandparent	Great-great-grandparent	Great-great-great-grandparent	Great-great-great-great-grandparent
Is the other person's ↓	Then they are your ↘
Parent		Sibling	Niece/​Nephew	Grandnephew/​Grandniece	Great-grandnephew/​Great-grandniece	Great-great-grandnephew/​Great-great-grandniece	Great-great-great-grandnephew/​Great-great-great-grandniece
Grandparent		Uncle/​Aunt	1st cousins	1st cousins once removed	1st cousins twice removed	1st cousins 3× removed	1st cousins 4× removed
Great-grandparent		Granduncle/​Grandaunt	1st cousins once removed	2nd cousins	2nd cousins once removed	2nd cousins twice removed	2nd cousins 3× removed
Great-great-grandparent		Great-granduncle/​Great-grandaunt	1st cousins twice removed	2nd cousins once removed	3rd cousins	3rd cousins once removed	3rd cousins twice removed
Great-great-great-grandparent		Great-great-granduncle/​Great-great-grandaunt	1st cousins 3× removed	2nd cousins twice removed	3rd cousins once removed	4th cousins	4th cousins once removed
Great-great-great-great-grandparent		Great-great-great-granduncle/​Great-great-great-grandaunt	1st cousins 4× removed	2nd cousins 3× removed	3rd cousins twice removed	4th cousins once removed	5th cousins

Canon law relationship chart

Canon Law Relationship Chart. See an example of how to use chart.

Another visual chart used in determining the legal relationship between two people who share a common ancestor is based upon a rhombus shape, usually referred to as a "canon law relationship chart".

The chart is used by placing the "common progenitor" (the most recent person from whom both people (A and B) are descended) in the top space in the diamond-shaped chart, and assigning a direction (arbitrarily, left or right) to each of the two people, A and B. Then follow the line down the outside edge of the chart for each of the two people until their respective relationship to the common ancestor is reached. Upon determining that place along the opposing outside edge for each person, their relationship is then determined by following the lines inward to the point of intersection. The information contained in the common "intersection" defines the relationship.

For a simple example, in the illustration to the right, if two siblings use the chart to determine their relationship, their common parent (either one, if there are two) is placed in the topmost position, and each child is assigned the space below and along the outside of the chart. Then, following the spaces inward, they would intersect in the "brother" diamond. If their children want to determine their relationship, they would follow the path established by their parents but descend an additional step below along the outside of the chart (showing that they are grandchildren of the common progenitor); following their respective lines inward, they would come to rest in the space marked "1st cousin". In cases where one side descends the outside of the diamond further than the other side because of additional generations removed from the common progenitor, following the lines inward shows both the cousin rank (1st cousin, 2nd cousin) plus the number of times (generations) "removed".

In the example provided at the right, generations one (child) through ten (8th great-grandchild) from the common progenitor are provided; however, the format of the chart can easily be expanded to accommodate any number of generations needed to resolve the question of relationship.

Additional terms

The following is a list of less common cousin terms.

Term	Definition	Example	Chart
Double cousin	Double cousins arise when two siblings of one family mate with two siblings of another family. The resulting children are related to each other through both of their parents and are thus doubly related. Double first cousins share both sets of grandparents and have twice the degree of consanguinity of ordinary first cousins; genetically, they are as related as half-siblings. In a scenario where two monozygotic (identical) twins mate with another pair of monozygotic twins, the resulting double cousins would test as genetically similar as brothers or sisters. Double second cousins can arise in two ways: from the relationships of two first-cousins with two other first-cousins or from the relationships two double-first-cousins with two other persons. May also be known as 'Cousins on both sides.'	Joseph and Julie are double first cousins because each is related through their mother's family and also their father's family, the result of a brother and sister (Helen and Eugene) having married another brother and sister (James and Mary). For Joseph and Julie, each has a mother who is an aunt by blood of the other and a father who is an uncle by blood of the other.	Gary Glenda Jason Beatrice James Helen Eugene Mary Joseph Julie
Half-cousin	Half-cousins are the children of two half-siblings, and their respective spouses.	Joseph and Lilian are half cousins because their parents (Helen and Charles) are half-siblings, their grandmother (Beatrice) having remarried.	Jason Beatrice Anthony James Helen Charles Janet Joseph Lilian
Stepcousin	Stepcousins are either stepchildren of an individual's aunt or uncle or nieces and nephews of one's stepparent.	Joseph and Rachel are stepcousins because Joseph's uncle (Eugene) has become Rachel's stepfather as a result of Rachel's mother (Corinda) having remarried Joseph.	Jason Beatrice James Helen Eugene Corinda Colin Joseph Rachel
Cousin-in-law	A cousin-in-law is the spouse of an individual's cousin or the cousin of one's spouse.	Joseph and Roger are first cousins-in-law to each other because Roger's wife (Julie) is Joseph's first cousin.	Jason Beatrice James Helen Eugene Mary Joseph Julie Roger
Maternal or paternal cousin	A term that specifies whether one individual is a cousin of another through the mother's side of the family (maternal) or the father's side (paternal). If the relationship is not equally paternal for both or equally maternal for both, then the paternal cousin of one is the maternal cousin of the other.	Julie and Natalia are maternal first cousins (being related through their mothers). Julie is also Joseph's maternal first cousin (as related on Joseph's mother's side), but Joseph is Julie's paternal first cousin (as related on Julie's fathers's side). Joseph and Natalia would only be related if they shared a common ancestor.	Jason Beatrice Gary Glenda James Helen Eugene Mary Maud Mark Joseph Julie Natalia

See also

• Collateral descendant
• Consanguinity
• Cousin marriage
• Family
• Parallel and cross cousins
• Sibling
• Second-degree relative

External links

• European kinship system
• Genealogy.com definition of various cousins
• Genealogy.com: What makes a cousin?
• Genetic Genealogy
• Family Relationship Chart