Usage notes

* People who have common grandparents but different parents are first cousins. People who have common great-grandparents but no common grandparents and different parents are second cousins, and so on.
* In general, one’s nth cousin is anyone other than oneself, one’s siblings or nearer cousins found by going back n+1 generations and then forward n+1 generations. One of my first” cousin’s ”parents” is one of my ”parents’ siblings”. One of my ”second” cousin’s ”grandparents” is one of my ”grandparents’ siblings .
* The child of one’s first cousin is one’s first cousin once removed; the grandchild of one’s first cousin is one’s first cousin twice removed, and so on. For example, if Phil and Marie are first cousins, and Marie has a son Andre, then Phil and Andre are first cousins once removed.
* In the southern US, the relation is considered the number of links between two people of common ancestry to the common aunt or uncle.
* A patrilineal or paternal cousin is a father’s niece or nephew, and a matrilineal or maternal cousin a mother’s. Paternal and maternal parallel cousins are father’s brother’s child and mother’s sister’s child, respectively; paternal and maternal cross cousins are father’s sister’s child and mother’s brother’s child, respectively.