Joe Kennedy III on Friday denounced his cousin Health and Human Services (HHS) Secretary Robert F. Kennedy Jr. as "a threat to the health and wellbeing of every American" in a blistering social media post. 

The rare public rebuke comes one day after RFK Jr.’s contentious Senate hearing, deepening a family feud that has fractured one of America’s most famous political dynasties.

Kennedy’s statement, viewed more than 1.2 million times, opens the curtain behind the extraordinary rift inside the political dynasty. 

Once synonymous with Democrat unity, the Kennedys are now split over RFK Jr.’s embrace of President Donald Trump and his appointment to HHS Secretary under a "Make America Healthy Again" agenda. Joe Kennedy’s demand that his cousin resign marks a dramatic escalation of the feud.

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In 2024, five of RFK Jr.’s siblings issued a joint statement blasting his endorsement of Trump as "a betrayal of the values that our father and our family hold most dear. It is a sad ending to a sad story." 

Caroline Kennedy later urged senators to block her cousin’s cabinet nomination, writing in a January 2025 letter that he was a "predator" who was "addicted to attention and power" and "unqualified" to lead HHS.

On Sept. 4, RFK Jr. appeared in a hearing before the Senate Finance Committee. Sen. Ron Wyden, D-Ore., accused him of firing CDC scientists and replacing them with "cranks" and "conspiracy theorists" who were "endangering children, leaving parents confused and scared."

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As Joe Kennedy wrote in his post, "None of us will be spared the pain he is inflicting… Those values are not present in the Secretary’s office. He must resign." 

His cousin Jack Schlossberg, President John F. Kennedy’s grandson, piled on in real time, mocking RFK Jr.’s testimony: "RFK LOSER is choking so badly LIVE."

With Robert F. Kennedy Jr.’s controversial tenure in Trump’s cabinet, the Kennedy dynasty’s divisions are now spilling into public view with some of the sharpest blows coming from within.

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The Department of Health and Human Services did not immediately respond to Fox News Digital's request for comment.

Christian McCaffrey’s availability is once again a big question mark for the San Francisco 49ers just days before their season opener against the Seattle Seahawks.

However, the running back himself doesn’t seem worried at all about whether he will play in Seattle on Sunday.

"I always plan to play," he told reporters, via ESPN. "I feel great about where I'm at. Unfortunately, when you have the injury history that I have, sometimes when you don't practice, things get blown out of proportion. But like I said, I feel great."

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McCaffrey was deemed questionable to play in the 49ers’ injury report on Friday due to a calf issue. He was listed as a limited participant at practice on Thursday, and after not practicing on Friday, fans are wondering if this is déjà vu after last year’s injury debacle.

McCaffrey was listed as questionable entering Week 1 last season, and he insisted he was fine and ready to play against the New York Jets. But he instead landed on injured reserve as his calf tightness turned out to be bilateral Achilles tendinitis. McCaffrey ended up playing just four games last season.

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So, as 49ers fans see a calf ailment again on the injury report, there is some skepticism leading into Sunday.

Head coach Kyle Shanahan didn’t go into detail about McCaffrey’s injury during his media availability, only confirming that he did not participate on Friday. McCaffrey, on the other hand, gave some background on what he was dealing with.

"I'm not supposed to go into anything that happened, but I felt like it was the smart thing to do to not finish the practice (Thursday)," McCaffrey said. "I've been there before and I've been my own worst enemy in situations like that, and I was proud of myself for not doing that again. Like I said, I went through a whole training camp. I feel great about where I'm at."

During training camp, McCaffrey didn’t have any injury issues, as Shanahan and others praised his performance in practice. He didn’t play in any preseason games for obvious reasons, as San Francisco wanted to be cautious.

But the season begins on Sunday, and the 49ers’ playoff hopes are tied to No. 23 performing like he did two seasons ago when the team reached the Super Bowl.

"At the end of the day, if you can play, you play in the game," he said. "It’s as simple as that."

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