There were a few relations: * John Adams, the second president, was the father of John Quincy Adams, the sixth president. * George Herbert Walker Bush, the forty-first president, was the father of George Walker Bush, the forty-third. * William Henry Harrison, the ninth president, was the grandfather of Benjamin Harrison, the twenty-third president. * James Madison, the fourth president, and Zachary Taylor, the twelfth, were second cousins.