I know such case (I'm in south of France).
The two sisters of a friend (disfellowshipped 6 months ago for apostasy --- Elders didn't like Raymond FRANZ lol ).
His first sister was very young, she was molested by the father, JW (about 30 years ago). Elders did nothing. The father is always JW. Her life is a hell.
The second sister, molestation was with the grand-father. But I don't know if he was JW.
It was a summmary, sorry I don't speak english very well....