These are the letters presidents leave to their successors

President Barack Obama waves as he leaves the Oval Office at the White House in Washington, Friday, Jan. 20, 2017. (AP Photo/Evan Vucci)

President Barack Obama waves as he leaves the Oval Office at the White House in Washington, Friday, Jan. 20, 2017. (AP Photo/Evan Vucci)

Becoming president of the United States is a unique challenge that only a handful of people alive have experienced firsthand. As such, it has been tradition for the outgoing president to leave a letter in the Oval Office for his successor.

President Donald Trump appeared at an event Sunday for swearing in new White House staff. He said former President Barack Obama had left him a letter as well and joked that he would keep it secret.

"We just went to the Oval Office and found this beautiful letter from President Obama," Trump said according to Business Insider. "It was really nice of him to do that. We will cherish that, we will keep that, and we won't even tell the press what's in the letter."

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Former president George W. Bush's 2009 letter to Obama was not released until last week when the National Archives made it public:

Jan 20, 2009

Dear Barack,

Congratulations on becoming our President. You have just begun a fantastic chapter in your life.

Very few have had the honor of knowing the responsibility you now feel. Very few know the excitement of the moment and the challenges you will face.

There will be trying moments. The critics will rage. Your "friends" will disappoint you. But, you will have an Almighty God to comfort you, a family who loves you, and a country that is pulling for you, including me. No matter what comes, you will be inspired by the character and compassion of the people you now lead.

God bless you.

Sincerely,

GW

Bill Clinton’s letter to George W. Bush:

January 20, 2001

Dear George,

Today you embark on the greatest venture, with the greatest honor, that can come to an American citizen.

Like me, you are especially fortunate to lead our country in a time of profound and largely positive change, when old questions, not just about the role of government, but about the very nature of our nation, must be answered anew.

You lead a proud, decent, good people. And from this day you are President of all of us. I salute you and wish you success and much happiness.

The burdens you now shoulder are great but often exaggerated. The sheer joy of doing what you believe is right is inexpressible.

My prayers are with you and your family. Godspeed.

Sincerely, Bill

Bill Clinton also received a letter from George H.W. Bush:

Jan. 20, 1993

Dear Bill,

When I walked into this office just now I felt the same sense of wonder and respect that I felt four years ago. I know you will feel that, too.

I wish you great happiness here. I never felt the loneliness some Presidents have described.

There will be very tough times, made even more difficult by criticism you may not think is fair. I'm not a very good one to give advice; but just don't let the critics discourage you or push you off course.

You will be our President when you read this note. I wish you well. I wish your family well.

Your success now is our country's success. I am rooting hard for you.

Good Luck — George

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