Washington (CNN) All five living US presidents attended George H.W. Bush's memorial service Wednesday, the first time since last year's inauguration in which Barack Obama, George W. Bush, Bill Clinton and Jimmy Carter were in the same place as President Donald Trump.

The novelty of what's commonly called "The Presidents' Club" is all the more intriguing because of the history that led each of them to the Oval Office. While most of the former presidents have made amends, they all reached office by criticizing at least one other member of the group to some degree.

That goes double for Trump, who lambasted both his predecessor Clinton and his 2016 opponent Hillary Clinton, and the icy lack of interaction between them Wednesday exemplifies that not all those wounds have -- or may ever heal.

Beyond their evolving feelings for one another, the presidents have all seen the public's feelings for them change in a positive direction.

Before he passed away, George H.W. Bush had the highest approval rating among that select group of living former presidents.

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