President Trump signed an executive order that makes recommendations about the childhood vaccine schedule and says that the measles, mumps and rubella (MMR) vaccine should be split into three separate shots. President Trump signed an executive order that makes recommendations about the childhood vaccine schedule and says that the measles, mumps and rubella (MMR) vaccine should be split into three separate shots. President Trump signed an executive order that makes recommendations about the childhood vaccine schedule and says that the measles, mumps and rubella (MMR) vaccine should be split into three separate shots. President Trump signed an executive order that makes recommendations about the childhood vaccine schedule and says that the measles, mumps and rubella (MMR) vaccine should be split into three separate shots. The American Academy of Pediatrics predicts it would take a decade to create a separate vaccine for each part of the MMR vaccine.