Conspiracy theorist Robert F. Kennedy, Jr. this week formally announced he would be running for the presidency as an independent -- and some members of his own family took the unusual step of formally denouncing him.

In a statement released on Monday, RFK Jr. siblings Rory Kennedy, Kerry Kennedy, Joseph P. Kennedy II, and Kathleen Kennedy Townsend condemned their brother's presidential run, which they said ran contrary to their own political values.

"The decision of our brother Bobby to run as a third party candidate against Joe Biden is a dangerous decision for our country," they wrote. "Bobby might share the same name as our father, but he does not share the same values, vision or judgement. Today's announcement is deeply saddening for us. We denounce his candidacy and believe it to be perilous for our country."

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RFK Jr., who for years has been best known for pushing false conspiracy theories about vaccines, has gained little traction in his efforts to unseat President Joe Biden as a candidate in the 2024 Democratic primary.

Since launching his campaign, Kennedy has made a number of controversial statements, most infamously his floating a conspiracy theory claiming that the novel coronavirus was genetically engineered to spare Ashkenazi Jews and Chinese people while being particularly harmful to "Caucasians and Black people."