I brought my daughter up as a single parent. Cannabis was the norm when socialising at home so she grew up around it … but like not licking her plate ! when at a friends house, there were some things we could do at home but would be discreet about when out.
She’s in her fourties now, a non smoker, fit woman who sailed through academia.
I have no doubt that some people who smoke are stoners in the stereotypical way and I expect they manage fine… I used to work in child protection a long time ago… dope was not an issue for me: crap parenting was the problem.
I have even brought rolled spliffs to a young woman in a birthing pool at the local hospital… she said it really helped… medicine!