President Biden had another embarrassing gaffe this week while singing "Happy Birthday" to the daughter-in-law of civil rights activist Martin Luther King.

The slip came as Biden was commemorating King at an annual breakfast event for race racketeer Al Sharpton's National Action Network.

Another Biden gaffe

Working the crowd, Biden said his wife Jill has a "rule" in his family, which is to sing happy birthday on people's birthdays.

But Biden appeared to blank on the name of Martin Luther King III's wife, which his Arndrea, while singing "Happy Birthday." Biden appeared to begin saying "Valerie."

Joe Biden forgets the name of the person he is singing Happy Birthday to. pic.twitter.com/hrkrhXehWT

— Townhall.com (@townhallcom) January 16, 2023

Biden, 80, is the oldest president in American history.

His frequent moments of confusion and irritability have raised concerns about his fitness for his role, concerns that may come under a magnifier as Biden reckons with the fallout of a damaging classified documents scandal that has rattled even reliable allies.

Biden the demagogue steps out

The audience at Monday's breakfast was treated to a long, pandering yarn about Biden's efforts to boost "equity" and close the "racial wealth gap."

Biden also attacked Republicans as "fiscally demented" and repeated his unsettling line about using F-15 warplanes against conservatives, quoting Thomas Jefferson with derision.

"I love my right-wing friends who talk about 'the tree of liberty is watered with the blood of patriots.' Give me a — if you need to worry about taking on the federal government, you need some F-15s," he said.

Kejanji Who?

A day earlier, Biden had paid homage to King at his former Atlanta church, where Democratic senator Raphael Warnock (Ga.) now preaches.

Biden could not resist capitalizing on the 94th anniversary of King's birthday to fire some partisan volleys, tying the civil rights movement to an ongoing struggle against "racism, extremism, and insurrection" -- sins Biden has often imputed to the nation's conservatives.

The speech was not without its awkward moments. Biden struggled to pronounce Supreme Court justice Ketanji Brown Jackson's name, which initially came out as "Kejanji Drown Jackson," and he drew laughter with the dubious claim that he attended a black church in his youth.

"Let’s lay one thing to rest.  I may be a practicing Catholic — we used to go to 7:30 mass every morning, in high school and going into college, before I went to the Black church.  Not a joke," he said.