Amendments are sent to the legislatures of the  states by default. Only one amendment, the 21st, specified a  convention. In any case, passage by the legislature or convention  is by simple majority.
Yes, there is a MMRV VIS, as well as a MMR VIS and a Varicella VIS. The law requires that a Vaccine Information Statement (VIS) be given out whenever certain vaccinations are administered, including MMR, varicella or MMRV vaccines.hen the first dose of measles, mumps, rubella, and varicella vaccines is administered at ages 48 months and older, use of MMRV vaccine generally is preferred over separate injections of MMR and varicella vaccines.
Children are given a second dose of MMR before they start school, usually between the ages of three and five, although the second dose can be given as quickly as three months after the first if there's an urgent need, such as in an outbreak.