Bad genes, on the other hand, is an entirely different issue. Don't even begin to blather to me that bad genes do not often also cause some very serious mental issues!
According to the WHO study, secondhand smoke is harmless, BUT no one, to my knowledge, ever suggested that smoking is good for you.
I have never understood the term “second hand smoke”. The smoke that comes off the burning end of the cigarette is no different from the smoke that the smoker inhales from the other end. That is “first hand smoke” and it is not good for any of us, it affects some much worse than others.