Here's a study referenced in the book. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6095578/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6095578/ The layman's

Here's a study referenced in the book. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6095578/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6095578/ The layman's explanation of the phenomenon is that parents observe a rapidly onset expression of gender dysphoria in their teenage daughters which "seemed to occur in the context of belonging to a peer group where one, multiple, or even all of the friends have become gender dysphoric and transgender-identified during the same timeframe."