I think being in a cult affects every one in a different way, some people are just more likely to be damaged by the experience. My daughter obsessed about being put in a concentration camp as a child, thanks to the experiences in the yearbook. While it's not good for anyone, some people are just more vulnerable.
I just got through reading a novel about a Mormon family with four children and what happens when the youngest daughter dies. It's very good, the culture of the Mormons is so similar to the JWs, it felt very familiar. The writer was a Mormon until age thirty, so it's was very true to how a belief system like that affects people.
You could see how the same teachings affect the different children in different ways based on age and personality. The oldest boy never bought into the faith, he struggles with having to pretend he believes he will see his sister again. The youngest boy had trouble accepting the death because he has been taught people can be resurrected and doesn't really understand that it can't happen right now. The older daughter worries excessively about making a mistake and not being worthy of the celestial kingdom and see her sister. The mother, who doesn't have a strong belief, goes into a deep depression and the father, a bishop, struggles with being there for his family while still doing his church work, and everyone feels guilty for what happened. The book is called a song for Issy Bradly by Carys Brady.