I posted about it again this morning on my Facebook page. It's a short story I wrote a few months ago about why Thomas Sowell wrote the book "Late Talking Children".
Short version: Sowell's son John didn't talk until he was almost four. The experts had a wall of diagnoses ready for him and not one of them fit. Years later, once John was grown, Sowell wrote about it in his newspaper column.
Parents started writing to him from all over the country. He had to ask himself... If so many people had this experience, why was there nothing out there for them to read? And so, he wrote the book himself. Late Talking Children.