There's a long running theme or discussion in right wing circles about this sort of phenomena:
With the exception of the last few years, the rates of Homosexuality and Transgenderism have been pretty consistent, single digit percentages of the population. The fundamental argument for Gay Liberation was that they were born that way, however the statistical likelihood (assuming that nurture/social environment is not a factor at all) of parents having 2 'queer' children is astronomically small.
To the point where it raises very serious refutation of that underlying assumption, it seems there is in fact a social component to this, and if there is - the Christian Right and those who oppose acceptance have a point - if it's a choice, then you can be judged for that choice.
Further to this - when a Mum comes out and says 'I have two Trans Kids' - all I hear is "I'm abusing my children" - not only that, I've heard multiple anecdotes from people that go along these lines:
Edit: At least you got your wish, I did read the book

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