"Instead of talking behind his back why not just say it to his face."

Alot will say 'its not my business' but i will say one way or another it is. If that person leads someone else astray it still seem not your business but this new bad fellow might end up leading yoir brother or sister astray. Now it has become your business (might take longer time) but if you have stopped him earlier it wont get that close. Now you stand the risk of getting your other siblings going astray too.

What a wise man you dad is. 💪 to all to wise dads out there wise enough to get their kids even wiser my dad too :)