Allowing 12-year-old children to make their own decisions about some matters indicates profound immaturity, not to mention stupidity.
They're children, not adults. I would no more permit my 12-year-old daughter to have a boyfriend (much less be alone with him, much less sleep with him) than I would permit my 2-year-old daughter to stick paper clips in an electrical outlet.
We were not talking about children. Rather, older teens and adults. You know that.