<< Your logic fails. Do both of your children have the same mother? If so, then by your logic they should both have asthma because they should have roughly the same genetic makeup. >>
No, my logic is solidified, actually. Both children have the same parents and are raised in the same environment. Therefore, if asthma is CAUSED by environmental factors (ie smoking) then both are gauranteed to get asthma. But, since one has asthma and one doesn't, then through their individual unique genetic makeup (They are not twins), Child #1 got the unfortuate chromosome/gene that will result in asthma and the other didn't get the chromosome/gene that causes asthma. It's genetic! And, there are studies that show that some of these genetic make up when exposed to environmental aspects put them into "action", but it's genetics.
Cancer research is going down this path. Just because I smoke 3 packs of cigarettes a day, does not mean I WILL get cancer or lung disease. I will however concede, that I loaded the cancer revolver with another bullet to play roulette with. Just like you will see that someone can contract lung cancer and never have come in contact with cigarette smoke or second hand smoke.
BTW, if second hand smoke CAUSES asthma then it must also TRIGGER an asthma attack? I can disprove that with my son too. I could put him in a car with the windows rolled up and he will NOT have an attack. I can put him in a room with mold and mildew and watch him suffocate to death!
