The discrepancy could prompt congressional action, but legal experts consider that unlikely under the Republican-led Congress

Robert F. Kennedy Jr. claimed the U.S. is doing “a better job than any country in the world” at curbing measles.

Newly obtained documents reveal that Robert F. Kennedy Jr. specifically told the Samoan prime minister the trip was to study the MMR vaccine.

Letters show Kennedy wanted to study Samoa's use of MMR vaccine