WASHINGTON, DC - AUGUST 10: Deputy Assistant to the President for Domestic Policy Dr. Heidi Overton (R), accompanied by Health and Human Services Secretary Robert F. Kennedy Jr. (L), speaks in the Oval Office before U.S. President Donald Trump signs an executive order calling for childhood vaccine shots to be spaced out into separate visits at the White House on August 10, 2026 in Washington, DC. During his second term, Trump has urged Health and Human Services Secretary Robert F. Kennedy Jr. to investigate further research on vaccines. (Photo by Anna Moneymaker/Getty Images)