I think your sister was right, to also see it in the context of their real childhoods, how deeply they were marked by their own experiences of deprivation and fear. I would like to know more about the Depression's effects in terms of psychology.
What alarms me is the problems we Boomers have, too. A whole different set. And our kids? Whew.
I think you are right, that Ns stopped growing. There's a desperate inflexibility in disordered personalities that disables their ability to respond to the present. Their negativity and loneliness is pitiful. Their selfishness is cell-deep and yet they think it's necessary. And it drives everyone away.
They are sad reflexive creatures, without reflection.
Maybe some Boomers, reflect too much. I wish it were possible to really see it all, like Buddha.
love,
Hops