Kyra Kennedy, 29, is the youngest daughter of health secretary nominee Robert F. Kennedy Jr.

Caroline Kennedy, daughter of former President John F. Kennedy, warned senators of her “predator” cousin ahead of his first confirmation hearing on Wednesday. In a letter first reported by The Washington Post, she wrote that his victims included family members and parents of sick children.

Kathleen "Kick" Kennedy is the eldest daughter of Robert F. Kennedy Jr., who could be confirmed as health secretary in Trump's administration.

Caroline Kennedy said in a scathing letter about her cousin, Robert F. Kennedy Jr., that she felt "an obligation to speak out."

Robert F. Kennedy Jr. faced aggressive questions about his skepticism of vaccines and other issues during the first of two scheduled Senate confirmation hearings.

As he seeks to lead the health department, Mr. Kennedy wore a thin tie dotted with feathered creatures to cap a classic suit.

Robert F. Kennedy Jr. will face the Senate for two days of confirmation hearings in a bid become the leader of Health and Human Services.

The health committee chairman, Sen. Bill Cassidy, R-La., also has expressed concerns about Kennedy's anti-vaccine work. A physician, Cassidy said earlier this month he “had a frank conversation” and “spoke about vaccines at length” with Kennedy. On Tuesday, Cassidy told reporters that he is still unsure if he is backing Trump’s nominee.

Robert F. Kennedy Jr. will stand before the Senate Finance Committee on Wednesday and the Senate Health, Education, Labor and Pension Committee Thursday as President Donald Trump's nominee to lead the Department of Health and Human Services.

The hearings were packed to capacity with protesters and fans, while the spillover crowd hung out in hallways and overflow rooms.