Alex Wong/Getty Images President Barack Obama (R) greets President Elect Donald Trump on the West Front of the U.S. Capitol on January 20, 2017 in Washington, DC.

Former President Barack Obama’s letter to President Donald Trump on Inauguration Day had four pieces of advice, CNN reported on Sunday.

After congratulating Trump on a “remarkable run,” Obama said that the two of them and their predecessors had been “blessed, in different ways, with great good fortune.”

“Not everyone is so lucky. It’s up to us to do everything we can (to) build more ladders of success for every child and family that’s willing to work hard,” Obama wrote.

Since receiving the letter, CNN reported, Trump has shown it to Oval Office visitors, as well as to people visiting his private White House residence. CNN received the letter from someone Trump showed it to.

Obama did not disclose the letter’s contents to his closest aides, according to CNN.

Obama also wrote in the letter that it was up to the president to demonstrate American leadership by maintaining the international order “that’s expanded steadily since the end of the Cold War.”

Third, he said, it was critical for Trump to leave politics aside and maintain the democratic institutions that form the backbone of American democracy, including rule of law, separation of power, equal protection, and civil liberties — institutions that “our forebears fought and bled for.”

Last, Obama recommended that Trump try and make time for friends and families despite the demands of the office.

“They will get you through the inevitable rough patches,” the former president wrote, before wishing Trump and incoming first lady Melania Trump success as they took over.

It has become customary for outgoing presidents to leave letters for their successors, and every president has done so since George H.W. Bush wrote one for Bill Clinton.

Obama and Trump have not spoken since Inauguration Day. Since then, Trump has lobbed a number of public criticisms at his predecessor and his policies, including the Affordable Care Act and Obama’s handling of Russia’s interference in the 2016 election.

Read Barack Obama’s full letter to Donald Trump at CNN >>

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