Society of Presidential Descendants

The Society of Presidential Descendants is an American lineage society for descendants of Presidents of the United States. The society was founded by Tweed Roosevelt, a great-grandson of U.S. President Theodore Roosevelt, and Massee McKinley, a great-great grandson of President Grover Cleveland and great-grandnephew of President William McKinley, to promote historic preservation and education on the legacies of American presidents.

Source: Wikipedia — Society of Presidential Descendants (CC BY-SA 4.0)