[["2 sets. John Adams was the 2nd U.S. President and his son John Quincy Adams was the 6th. George H.W. Bush was the 41st U.S. President and his son George W. Bush was the 43rd.", 127.0], ["Only two families have achieved that distinction - the 2nd and 6th Presidents the Adams, and the 41st and 43rd the Bush\u2019s.", 91.0], ["Two pairs. John Adams and John Quincy Adams as the 2nd and 6th. George H. W. Bush and George W. Bush as the 41st and 43rd.", 69.0]]
how many father son presidents have there been
history,presidents