Updated

Members of the iconic Kennedy family, a longtime staple in American politics, announced a major endorsement in the 2024 presidential race on Thursday — a move that came as a snub to one of their own seeking the White House.

Half a dozen Kennedy family members appeared alongside President Biden at an event in Philadelphia to publicly back him over Robert F. Kennedy, Jr., who is driving Democrats to panic that his independent White House bid could lead to a victory for former President Donald Trump.

"President Biden has been a champion for all the rights and freedoms that my father and uncles stood for," RFK Jr's sister, Kerry Kennedy, said during the event, referencing the late former President John F. Kennedy, the late former U.S. Attorney General and New York Sen. Robert F. Kennedy, and the late former Massachusetts Sen. Ted Kennedy.

2 KENNEDY CHILDREN ENDORSE OPPONENT OF PROGRESSIVE LOS ANGELES DA, CITE PAROLE HEARING FOR RFK'S KILLER

Presidential candidates

Former President Donald Trump, independent presidential candidate Robert F. Kennedy, Jr., and President Biden. (Getty Images)

Kerry Kennedy went on to praise what she described as Biden's accomplishments during his first term, and claimed that Americans' quality of life had improved under his presidency. She then blasted Trump, claiming he would be a "dictator" if elected.

She then introduced Biden despite reports that former Rep. Joe Kennedy III, D-Mass., who ran a failed campaign for U.S. Senate in 2020, and currently serves as Biden's special envoy to Northern Ireland, was expected to make the introduction. He did not appear on the stage alongside his family members.

Reports also said the family members were expected to put in some work on behalf of the Biden campaign in Pennsylvania, a major swing state, following the event, including making calls and knocking on doors.

When reached for comment, Kennedy's campaign pointed Fox News Digital to a statement the candidate made on social media just ahead of the event.

"I hear some of my family will be endorsing President Biden today. I am pleased they are politically active — it’s a family tradition. We are divided in our opinions but united in our love for each other," RFK, Jr. wrote. "I hold this as a possibility for America too. Can we disagree without hating our opponents? Can we restore civility and respect to public discourse? I think we can." 

TRUMP THREATENED WITH JAIL IF HE MISSES HUSH MONEY TRIAL AS BIDEN CAMPAIGNS IN PENNSYLVANIA

Joe Kennedy III

Former Rep. Joe Kennedy III, D-Mass., speaks onstage during the Robert F. Kennedy Human Rights Hosts 2019 Ripple Of Hope Gala & Auction In NYC on December 12, 2019 in New York City. (Mike Pont/Getty Images for Robert F. Kennedy Human Rights)

"My campaign, which many of my family members are working on and supportive of, is about healing America — healing our economy, our chronic disease crisis, our middle class, our environment, and our standing in the world as a peaceful nation. But this will only happen if we heal our national conversation, and move from rage and fear into love and respect," he added.

The announcement marks the latest and most forceful rebuke of RFK, Jr. by members of his family after they described his candidacy as "perilous for our country" last October following his decision to run as an independent instead of a Democrat.

They've also been critics of his past comments concerning the COVID-19 pandemic, which he once suggested was engineered to target certain ethical groups.

Last month, the Democratic National Committee launched an effort to silence the threat to Biden's re-election from third-party candidates, namely Kennedy, in the form of a team that is expected to actively combat them with legal challenges and opposition research.

BIDEN TAKES HEAT OVER STRANGE CANNIBAL STORY: ‘LIKE SOMETHING OUT OF A BAD SCRIPT'

Robert F. Kennedy, Jr.

Independent presidential candidate Robert F. Kennedy Jr. speaks at a Cesar Chavez Day event at Union Station on March 30, 2024 in Los Angeles, California. (Mario Tama/Getty Images)

Since its inception, members of the team post near constant criticism of RFK, Jr. on social media, and have frequently referred to him as a "spoiler" candidate. They have also claimed Kennedy is in cahoots with Trump in order to help him win.

Earlier this month, the DNC accused RFK, Jr's campaign of acknowledging its role as a "spoiler" after a woman associated with the campaign was captured on video discussing campaign strategy and how Trump could win the state of New York with the independent candidate on the ballot in November.

CLICK HERE TO GET THE FOX NEWS APP

"The only way that Trump can even, remote possibility of taking New York is if Bobby is on the ballot," a self identified Kennedy campaign staffer, told a room of Republicans in New York in a video reviewed by Fox News Digital.

"If it’s Trump vs. Biden, Biden wins. Biden wins six days, seven days a week. With Bobby in the mix, anything can happen."

Fox News' Andrew Mark Miller contributed to this report.

Get the latest updates from the 2024 campaign trail, exclusive interviews and more at our Fox News Digital election hub.