Members of the Kennedy dynasty explain why they will not support anti-vaxxer Robert F. Kennedy Jr. 2024 presidential bid against Biden

• Robert F. Kennedy Jr. is challenging President Joe Biden for the 2024 Democratic nomination.
• Members of his famous family say they oppose his candidacy because of his anti-vaccine views.

Members of the Kennedy family say they are not supporting Robert F. Kennedy Jr's bid for the 2024 Democratic presidential nomination because of his prominent role in the anti-vaccine conspiracy theorist movement.

The nephew of former President John F. Kennedy officially announced his long-shot bid to challenge President Joe Biden for the nomination at an event in Boston on Wednesday.

Kerry Kennedy, one of his sisters, told Insider in a statement that she will not be supporting her brother's bid.

"I love my brother Bobby, but I do not share or endorse his opinions on many issues, including the COVID pandemic, vaccinations and the role of social media platforms in policing false information," she said.

Kennedy built a reputation as a prominent anti-vaxxer long before the pandemic, but his impact reached new heights when the COVID-19 pandemic began in 2020.

One report identified him as being one of 12 people who were responsible for the spread of most disinformation about COVID-19 online.

Kennedy, who graduated from Harvard and previously worked as an environmental lawyer, has repeatedly courted controversy for his statements about vaccines.

He has pushed a widely debunked claim that vaccines are linked to autism, and last year likened government efforts to contain COVID-19 to Hitler's Germany.

His anti-vaccine group, Children's Health Defense, was removed from Facebook and Instagram last year and his personal Instagram account was also barred in 2021.

"I love my uncle and admire him for many reasons," his niece Kerry Meltzer, the daughter of his sister Kathleen Kennedy Townsend, said in a statement to Insider.

"But I'm a physician who has seen the life-saving power of vaccines firsthand, particularly the COVID vaccine, and I think Bobby's vaccine scepticism is unfounded and potentially dangerous. As a result, I will not support his candidacy for president. I will be supporting President Joe Biden."

His campaign did not respond to Insider's request for comment.

This family schism is not new – in 2019, two of his siblings and a niece penned an op-ed for Politico in which they denounced his views on vaccines and their "heartbreaking consequences."

It is perhaps unsurprising to see many of the Kennedys oppose his candidacy. Not only have family members long opposed his views on vaccines, three of his siblings are diplomats for the Biden administration.

Kennedy poked fun at his family's lack of support as he addressed the ballroom full of people at the Boston Park Plaza hotel.

"There are other members of my family who are not here today," he said to laughter.

"I know most American families, they never have any differences with each other. So when that happens in a family, it's really huge news, like, everywhere."

He added that he has "no ill will" towards any of his family members and said that many of his relatives had written him "beautiful letters of love."

While his siblings were notably absent, several of his children and grandchildren attended the campaign launch.

Although Biden is yet to confirm whether he will run again in 2024, The Washington Post and The New York Times have reported that a campaign launch could be as early as Tuesday.

Self-help author Marianne Williamson has also said she will challenge Biden for the Democratic nomination.