President Biden seemed to forget Arndrea Waters King's name while singing Happy Birthday to her on Monday during a speech at the National Action Network’s annual Martin Luther King Jr. birthday breakfast.

"Well my wife has a rule in my family, when it's somebody's birthday, sing Happy Birthday," he said before he started singing to the wife of Martin Luther King III, the civil rights leader's eldest son.

Biden appeared to forget King's name in the final verse before quickly moving on. He began the song as the audience chimed in, but as he got to the portion with her name, he appeared to say "Happy Birthday, dear Valen," trailing off.

"Well, it's hell turning thirty, but you've got to put up with it," he said. 

President Biden

President Biden sings Happy Birthday to Arndrea Waters King on Monday.  (Screenshot/WhiteHouse)

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Biden's gaffe amused social media, with the mistaken song going viral on Twitter Monday.

Rev. Al Sharpton introduced Biden at the event and said that the president and Vice President Kamala Harris have "literally brought about things" that have changed the lives of all Americans in the last two years. 

"It's an honor to spend the King holiday with the National Action Network and the King family," Biden began. "Martin the third, understand that we celebrate the legacy of your beloved father and mother and they worked for the beloved community."

Biden also delivered remarks at Martin Luther King Jr.’s historic Ebenezer Baptist Church in Atlanta Sunday. 

"Folks, you know, on this day of remembrance, as we gather here at this cherished Ebenezer to commemorate what would’ve been Dr. King’s 94th birthday, we gather to contemplate his moral vision and to commit ourselves to his path — to his path.  The path that leads to the ‘Beloved Community,’ to the sacred place and that sacred hour when justice rains down like waters and righteousness was a mighty stream," he said during the remarks. 

President Biden

President Joe Biden gestures boarding Air Force One at Nantucket Memorial Airport in Nantucket, Mass., Sunday, Nov. 27, 2022. Biden is heading back to Washington after spending the Thanksgiving Day holiday in Nantucket with family. (AP Photo/Susan Walsh) (AP Photo/Susan Walsh)

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The president repeated a claim that he frequented a Black church during the civil rights movement during his speech on Sunday.

"Let's lay one thing to rest. I may be a practicing Catholic, but [I] used to go to 7:30 Mass every morning in high school and then in college before I went to the Black church," the president said. 

He addressed former U.N. ambassador and former Southern Christian Leadership Conference executive director Andrew Young and said he was one of the "greatest we've ever had."

Biden Austin Blinken

WASHINGTON, DC - JANUARY 5: Flanked by Secretary of State Antony Blinken (L) and Secretary of Defense Lloyd Austin (R), U.S. President Joe Biden speaks during a cabinet meeting in the Cabinet Room of the White House January 5, 2023 in Washington, DC. (Photo by Drew Angerer/Getty Images) (Photo by Drew Angerer/Getty Images)

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"Andy and I took on apartheid in South Africa and a whole lot else. They didn’t want to see him coming. But we used to – that's when we would organize to march and to desegregate the city," Biden said.