Mandates = government intrusion
Perry had no problem with it even though there was a legislative solution. Apparently Perry and his wife think they know better than parents.
The Legislature had delegated the authority to mandate vaccines to the Executive Branch years before.
The Legislature mandated a named core of 5 vaccinations (diphtheria, rubeola, rubella, mumps, tetanus, and poliomyelitis) in the original law, and delegated the authority to the DSHS to name others. http://www.statutes.legis.state.tx.us/Docs/ED/htm/ED.38.htm
The head of the DSHS is the Governor, who is the Executive Officer of the State, and names the Director of DSHS with approval by the Senate.