Robert F. Kennedy Jr.'s sister says that she feels heartbroken over having to oppose her brother's presidential ambitions but feels honor-bound to do so.

"I love Bobby," Kerry Kennedy told The New York Times. "It’s heart-wrenching to be in this position."

At a recent campaign event in Philadelphia, Kerry appeared alongside other members of her family to lend their support to President Biden and argued the country could not afford another Donald Trump term. Both major tickets have signaled fear that Kennedy's insurgent campaign could play spoiler. 

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Robert F. Kennedy Jr., Joe Biden Kerry Kennedy split image

Robert F. Kennedy Jr.'s sister, Kerry Kennedy, is publicly opposing her older sibling's bid for president and supporting Joe Biden. (Getty Images)

"In the end, why is he out there doing this?" Kerry told the Times of her brother's independent presidential run. "For the same reason I’m out there. Because we both believe the stakes are high."

"Nearly every single grandchild of Joe and Rose Kennedy supports Joe Biden," Kerry told an audience at a Biden campaign stop in Philadelphia.

"That’s right: The Kennedy family endorses Joe Biden for president," she said, according to the Times report. "President Biden has been a champion for all the rights and freedoms that my father and uncles stood for."

"I am pleased they are politically active — it’s a family tradition," RFK Jr. responded at the time. "We are divided in our opinions but united in our love for each other." 

Another Kennedy family member, Christopher G. Kennedy, told the Times that Kerry "feels a special burden" in opposing RFK Jr.'s candidacy. 

"She has supported hundreds of human rights activists around the world," Christopher said. "Her abilities would be diminished if the Kennedy name is associated with fringe thinking, crackpot ideas and unsound judgment."

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Robert F. Kennedy Jr.

Another Kennedy family member, Christopher G. Kennedy, told The Times that Kerry "feels a special burden" in opposing RFK Jr.'s candidacy.  ( Emily Elconin/Getty Images)

Kennedy's controversial stances on vaccines and embrace of conspiracy theories have helped make him a pariah in the media and his old Democratic Party home.

RFK Jr. has rejected accusations that he is anti-vaccine and gained increased scrutiny for his views on public health during the COVID pandemic

The candidate said in 2023 that he would prosecute Dr. Anthony Fauci for his actions during the pandemic, should his attorney general find that he was guilty of wrongdoing. 

Christopher Kennedy told The Times that he was constantly criticized by people in public over his brother's candidacy for president. 

"People confront me at the grocery store — ‘Why are you letting your brother get away with this?’" Christopher said. "I think we will all get blamed if Bobby causes this outcome to occur."

"I would say that, like all true believers, he is unreachable," he told the outlet. "That hardening of the shell has definitely occurred."

RFK Jr.'s campaign did not respond to a request for comment from Fox News Digital

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