John Tyler, the 10th president of the United States, has two living grandchildren.

Tyler (1790-1862) was 63 when he fathered his seventh son, Lyon Gardiner Tyler, in 1853. And Lyon was in his 70s when he fathered two boys, Lyon Gardiner Tyler Jr. in 1924 and Harrison Ruffin Tyler in 1928. (Harrison, now 84, owns Sherwood Forest, the Virginia plantation that his grandfather purchased in 1842.)

This makes Tyler the oldest U.S. president with living grandchildren. Second place belongs to James Garfield, who was 41 years younger than Tyler.

(Thanks, Arnold.)