With the death of George H. W. Bush, we can make many comparisons with John Adams.
Both were born in Massachusetts.
Both served as Vice President under their Presidents for eight years, John Adams under George Washington, and George H. W. Bush under Ronald Reagan.
Both only had one term as President, defeated for reelection.
Both are seen as lower in ranking than their predecessors, George Washington and Ronald Reagan, who served two terms in office.
Both had the President elected after them rank higher in rankings of Presidents, and both Thomas Jefferson and Bill Clinton served two terms in office.
Both outlived their wives.
Both had a son become President, and live to see that occur.
Both reached to the age of 90, with Adams being the longest lived until Ronald Reagan, then Gerald Ford, then George H. W. Bush, and then Jimmy Carter surpassed his age.
Bush died at the oldest age of any President, although Jimmy Carter could surpass Bush if he lives to March 22, 2019.
Both died after 25 plus years in retirement.
Both have been rated higher than their son, John Quincy Adams and George W. Bush, in rankings of historians and political scientists, and it is unlikely that their sons will ever surpass them.