I also do not know the percentages of healthy people who end up contracting end-stage kidney disease. It would appear to be quite small, however (how many people do you know personally who went from good health to requiring a kidney transplant)? I imagine that most people, if they were bothered by this issue, thought as I did (and I have seven children, BTW); namely, that I would rather definitively save a life now as opposed to the remote possibility of saving the life of one who is closer to me in the future. Even if you knew the exact numbers, there is no guarantee that your children won't fall into that tiny minority. Clearly, however, this is an issue that one must deal and come to terms with before donating.