Bingowings said:
That doesn't mean that every child born to and raised by depressive parents is going to be the same it just makes it more likely.
Child's mental development is not subject to any genetic al inheritance from the parent. There is just no evidence what so ever that a child will be a good composer/writer/painter because the parents were.
As I said... the factor may be parent's social influence after the birth. Not any kind of inheritance.
Bingowings said:
So the only source for this family strength that Ben and Vader hopes to use against the Emperor and Palpatine fears is genetic.
Didn't I just go through this? The family strength that Ben hopes to use is his ability to trigger Anakin's return. While Vader was purely after Luke's powers (which doesn't have to have anything to do with them being related). Vader only tried to exploit the fact that Luke was his son as social tool to accelerate his turning to the dark side.