Robert F. Kennedy's nomination will put Republican lawmakers' loyalty to the test, as the former Democrat holds a range of unorthodox positions that could alienate both conservatives and liberals.

Cassidy is expected to challenge RFK Jr. on his vaccine skepticism and views on public health in today's confirmation hearing.

Caroline Kennedy, the daughter of former President John F. Kennedy, posted a video reading a scathing letter to senators about her family member, in which she called Trump’s nominee to lead the Department of Health and Human Services (HHS) a “predator” who is distorting his father’s legacy to “advance his own failed presidential campaign.”