Now he trying to screw up my Grandkids Health! President Donald Trump on Monday signed an executive order calling for revamped childhood vaccine recommendations that promote his long-held but discredited theory that childhood shots should be spaced out into separate medical visits. He is pushing the non-science notion that separating the measles, mumps and rubella (MMR) vaccine into three different single-disease shots and administering all childhood immunizations at separate appointments whenever possible is suppose to be a good think.