Without knowing when you, yourself are going to leave this Earth, if you were able to donate a portion of your life [hour, day, year, etc.] to a loved one as you can now donate a kidney, would you?
I would, if I knew I would die shortly. After all I would die and there was nothing I could do. I’d say the maximum amount I would be willing to donate is a year – yeah, if I knew I would die in a year.