Depends on the personal relationship that your spouse has with that distant relative. If they are very close, that is one thing, but if said distant relative is seen once a year at the family reunion I would not. Further, what is the lifestyle of that distant relative? Are they abusing booze, doing other things that trashed their kidneys, or are they in need of a kidney through no fault of their own?
It is not a simple question, with no definitive answer. Depending on the variables involved with the specific case, my decision could vary. One thing I can tell you for sure...if someone(s) are trying to GUILT me into giving up one of my kidneys, they are going to die waiting on me to give it to them, as it is not going to happen.