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.

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

The public dispute between Robert F. Kennedy Jr. and Caroline Kennedy has the political family back in the spotlight. Meet key members of the Kennedy family.

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

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

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.

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

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