Actors Ben Affleck and Matt Damon who are very close friends, are also cousins, the Boston Herald reported on Friday.

Affleck and Damon are 10th cousins, according to the New England Historic Genealogical Society, the oldest genealogy research center in the U.S.

The actors share in common a 10th-grade grandfather named William Knowlton of Ipswich, a bricklayer who died in 1655, the paper noted.

The actors are related on their father's side.