I have had the opportunity to sabotage the belief in the JW cult by older, entrenched JW family. I will never know if my efforts would have born fruit or not because I never really engaged in any serious deprograming efforts.
It is a choice that can reveal a lot about one's character. Not that I have such sterling character, but I cannot find the motivation to throw a stick into the spokes of a good person who's entire life is built around the JW cult.
Many seem to be happy and coping. They can get excited over a few earthquakes, enjoy a nice "jack 'em up, shoot 'em out" District Assembly rally and then seque back into the comfy doldroms of everyday JW la de da routine. I have a quite elderly aunt and uncle who have been staunch JWs since birth. They are now 69 and 88 respectively with children and grandchildren in the Org.. I am content that I can visit with them by phone and the net as often as I want.
If I started to work the JW angle it would be a waste of time It would destroy my ability to have contact with them and the worst case scenario would be if I actually put doubts in their minds and put them in the position of doubting their core beliefs in the twilight of their life.