Yes. There is no shortage of volunteers who wish to donate a kidney. Typically, when a kidney patient is in a secure family, as many as five family members volunteer as organ donors. However, many live organ donors are disqualified. Possible donors go through an intense screening process and thorough medical exam. Reasons for disqualification are many, and often beyond the volunteer's control. Just a few examples: Insufficient "matches" in the initial blood testing. If your body chemistry doesn't match the recipient's, there is too great a risk the recipient will reject the new kidney. Grandparent had diabetes. That means the donor is high risk of contracting diabetes. Diabetes causes kidney failure. Lifestyle. Consumption of narcotics, alcohol, or prescription drugs result in disqualification. Previous medical conditions, or problems with current health. One thing the doctors do not want is TWO renal patients. It is true that the human body can live normally with only one kidney. In fact, the one kidney even grows in time to handle the load. There is a lot of reserve effort available; even if only one kidney is functioning at a dimished capacity, a person may have no trouble. However, if the doctors determine that the volunteer cannot live normally on only one kidney, then the donor is disqualified. Most often, though, renal donors are disqualified because their organs are unsuitable for that one, specific, individual patient. This is why there is a shortage of kidneys available for transplant.

I don't know. Ask the zombies.

B.C. Canada has a living donor kidney organisation. I am not sure how long it has existed but it sure is a good idea.