The man who hopes to be President Donald Trump's health secretary said he needed to see data showing vaccines are safe, but when an influential Republican senator did so, he dismissed it.

Robert F. Kennedy Jr.’s nomination to be the nation’s top health official is uncertain after a key Republican joined Democrats to raise persistent concerns over the nominee’s deep skepticism of routine childhood vaccinations that prevent deadly diseases.

R obert F. Kennedy Jr., President Trump’s pick to head the U.S. Department of Health and Human Services (HHS), was grilled by Democratic senators during his confirmation hearing on Jan. 29 and Jan. 30, who confronted him with conspiratorial and conflicting statements he has made about COVID-19.

Kennedy’s bid to serve as America’s top health official may be decided by a handful of Republicans, including several senators who questioned him Thursday.

Robert F. Kennedy Jr. spent two days this week insisting to senators that he’s not anti-vaccine. He said that he instead supports vaccinations and will follow the science in overseeing the $1.7 trillion Department of Health and Human Services, which, among other duties, oversees vaccine research, approval and recommendations.

The former U.S. ambasador — the last surviving child of Jacqueline and John F. Kennedy — urged lawmakers to reject RFK Jr.’s nomination as health secretary.

Kennedy, a Democrat who ran as an independent but ended up supporting Trump in the 2024 presidential campaign, was grilled by senators over his views on vaccines, abortion, Medicaid and more during two days of confirmation hearings.

Caroline Kennedy, a member of the famed U.S. political family, urged senators on Tuesday to reject her cousin Robert F. Kennedy Jr.'s nomination to lead the top U.S. health agency, calling him a "predator" and his healthcare views "dangerous.

Robert F. Kennedy Jr. is facing his first Senate confirmation hearing as President Donald Trump's nominee to be the secretary of health and human services.