Robert F. Kennedy Jr.'s long record of questioning the safety of childhood vaccinations persisted as a flash point for him Thursday during a confirmation hearing where a key Republican quickly raised concerns about his views.

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.

Robert F. Kennedy Jr.’s confirmation hearings made clear that he is unqualified to be HHS secretary even beyond his positions on vaccines, writes Dr. Georges C. Benjamin, executive director of the American Public Health Association.

Robert F. Kennedy Jr. has admitted to the US Senate that he has reached at least one settlement agreement in which he was accused of misconduct or inappropriate behavior.

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.

What to know from Robert F. Kennedy, Jr.’s hearings before the Senate Finance Committee on Wednesday and the Senate Health, Education, Labor, and Pensions on Thursday.

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.

RFK Jr. claimed he is not “anti-vaccine” and appeared unfamiliar with key aspects of healthcare insurance programs in his confirmation hearing.