Ah, but see what you did? You brought up its benefits. That just closes their minds to you. It's the wrong argument to make. Unless they've been told that their child needs medically supervised cannabis treatment, they don't care what you say.

But if you make them understand that it's available now at the drop of a hat, that the only thing that legalization changes is the quality of the source and the product, they can grapple with a rational issue.