evidence: What to know about RFK Jr., the controversial conspiracy theorist who ran for president and joined Donald Trump's campaign - Robert F. Kennedy Jr., 70, is John F. Kennedy's nephew. [...] Robert F. Kennedy Jr., an environmental lawyer who has promoted baseless public-health conspiracy theories and anti-vaccine misinformation, dropped out of the presidential race in August and endorsed Donald Trump. Trump went on to add Kennedy Jr., along with Tulsi Gabbard, to his transition team to help shape his administration if he wins the election in November. [...] Robert F. Kennedy Jr. is a member of one of America's most famous political dynasties.