Sister shouldn't play the role of parent to marijuana-smoking brother

Q. I'm a 23-year-old woman living across the country from my family, and my brother "Justin" is an 18-year-old high school grad. Justin is living at home and working, and might go to university next year.

My parents just called to share that he has been caught with marijuana multiple times, always with friends, and most recently by the police.

My parents asked me to talk to him. Their moral code is that weed is bad, and that to do nothing would be to absolutely shirk their religious and moral responsibilities as parents. I totally understand that they love him and want to see him flourish, and getting caught with weed could cause major consequences.

My parents feel they can't convince Justin to stop smoking, partly because he has a tendency to immediately "shut down" during hard conversations, but mostly because they're his parents and he just doesn't listen to them. They believe if the message came from me, he would listen, because we have a good relationship and he respects me.

I'm inclined to help them, to help Justin, but I don't want to drive him away or act like a third parent. My hope is that I can offer to be a listener and translator instead of a messenger.

How can I do this in a way that will communicate my love and concern, not make me feel so terrified, and help him share his feelings instead of shutting down?

Sister, Not Parent

A. Your parents are asking you to cross a boundary, and to indulge them will cross a boundary no matter what helpy glitter or listeny ribbons you apply.

Be a sister. That's your prerogative, your job and your place. It can also involve all the listening and loving and even WTH-ing you feel moved to supply in the course of your normal relationship with Justin. But not as anyone's agent.

The problems here predate the weed anyway, and are possibly the soil in which it grew (if you will). You say Justin shuts down for hard conversations let's call that "2" and your parents' weed is bad/"religious and moral responsibility" code-orientation hints at an authoritarian parenting style. Authoritarian meaning a strict set of rules and expectations that'll be followed, no discussion.

If true, that's the other "2": 2 plus 2 equals Justin has been trained either to live exactly as his parents expect, or to make sure any deviations from their rules are on the sly and undiscussed.

Dialogue won't spring from this dynamic naturally. Because what's to discuss in "their moral code is that weed is bad"?

Tell your parents no, you won't intervene.

In case they ask your advice: If they want Justin to talk, then they need to listen.

If they want to do the talking, then they can expect deaf ears.

If they want a loophole, through you or otherwise, then they need to accept there isn't one.

If they just want a weed-free household, then they need to ask Justin to quit using or move out.

And if they want to know why they're losing their grip on their son, then they need to rethink "grip." For any parent and (adult) child, and for any two humans.

Maybe raising that topic with Justin is a way to open him up.

• Email Carolyn at tellme@washpost.com, follow her on Facebook at www.facebook.com/carolyn.hax or chat with her online at noon Eastern time each Friday at www.washingtonpost.com.

© 2018 The Washington Post