The government should not be involved with things like that with the family of a married couple. I know that even many libertarians do believe that so long as we have a government it should take care of other peoples’ kids so you don’t have to resent others’ ways of dealing with their kids.
If these are poor populations then we’re getting those kids’ medical bills; at least put the seat belts on so I don’t have to pay for that.
I’m surprised that anyone would oppose such a measure; it is like letting drivers talk on cell phones as far as the danger involved.