First cousin

First cousins are the children of two siblings, so they share one or both grandparents. Older records often say only cousin, or cousin-german, for the same relationship.

The counting rule for every cousin degree starts here. Find the closest ancestor two people share and count the generations down to each of them. If the nearer person is a grandchild of that ancestor, they are first cousins; a great-grandchild makes them second cousins; each extra great adds one to the number. If the other person is further down, the cousins are also removed (see Removed).