What are parents to do? Get their kids spayed and neutered? Of course then they will never become grandparents.
I have a friend who obsesses over this - but after having appropriate talks and supervision, what good does that do? Eventually, nature is gonna takes its course. Even if you try to micro-manage 95% of their time, there’s that pesky 5%.
I don’t remember many details of the conversations, mostly my father putting the fear of god in me to ever be caught in our house alone with a girl when I was in HS. Also he stressed how my life would be ruined if I got a girl pregnant...I believed him.