Those who do not believe that child-rearing can have a profound effect on the courses of the lives of millions might take a look at the book Soul Murder by Morton Schatzman. (I think there is more than one book with that title.) It is the story of Daniel Gottlieb Mortiz Schreber (1808-1861), whom the book jacket describes as "a leading German physician and pedagogue, whose studies and writings on child-rearing techniques strongly influenced those practices during his life and long after his death..." He was apparently Hitler's favorite pedagogue.

The book compares the writings of Schreber and one of his sons, in order to elicit some understanding of the son's descent into what would be diagnosed as paranoid schizophrenia, I think. The useful thing about the Schrebers is that they both wrote extensively, and their writings are preserved. One can wonder what influenced the elder Schreber, but evidence about that is scanty or non-existent.

I am not saying that all cases of schizophrenia are due to exactly the same causes as this one -- at least not as drastically so. I still think it is worth reading as at least a clue.