Being a smoker/grower doesn't make you irresponsible. Your actions toward your kid/s that determines that.
We've got 7 kids aged between 10, 11, 16, 19, 20, 23 and 24.
Of the four eldest, only one is a regular smoker. One is a casual smoker, one smokes very occasionally and the other doesn't smoke at all. Curiously, that breakdown corresponds to their ages from oldest to youngest. I'd assume that the 16 year old has smoked. She drinks on occasion.
The two youngest obviously have had limited exposure to cannabis culture.
We tend to keep our smoking hidden from the youngest kids for a few reasons:
Schools have standard anti-drug education program that encourages children to tell someone if their parents 'are doing drugs'. We educate at home about the medicinal benefits of cannabis and uses of hemp if and when the subject arises.
One of our ex partners would take great delight in claiming that we were unfit parents due to our illicit drug use.
Education
We *always* explain our beliefs about cannabis based on our experiences and research into medicinal use. We also extol the virtues of industrial hemp to all our kids when any environmental discussion arises.
When our youngest two reach their teens, we'll explain our position in respect to smoking cannabis based on our knowledge. We have done the same with the other five.