is it unreasonable to wonder how someone got the sickness tho XD
i had this pretty much but then had to leave it noOOooO its ok tho there positives and negatives in this case
Are they eating the right foods, taking proper hygienic steps, cleaning and sanitizing their home regularly, having anyone who visits the home do the same thing, taking those steps going out into public where germs exist everywhere, how strong of an immune system, the questions continue to go on for each person that comes into contact/near the other party, etc.
The answer to your questions are clearly no and even if you do everything right sickness will still occur, but you can take steps to live a cleaner and more sanitary lifestyle to lower the possibility.
Where sickness doesn't exist is in heaven with the father outside of this earthly realm.