Boot-strapping types who believe that surmounting a difficult childhood is mainly a matter of will may be perplexed by an anecdote near the beginning of Nadine Burke Harris’s new book, “The Deepest Well: Healing the Long-Term Effects of Childhood Adversity.”

In it, the pediatrician describes a 7-year-old boy named Diego, who showed up at her Bay Area clinic looking like an undersized 4-year old. He had been referred by a school nurse for suspected ADHD. But Burke Harris also noted that her young patient had patchy skin and a chronic wheeze. A few probing questions of his mother unleashed a torrent of information. Most significantly, Diego had been sexually abused by a family friend when he was, yes, 4 years old. He hadn’t grown since.

In her book, Burke Harris boils down two decades of research showing the ways that early trauma — what she calls toxic stress — can trigger hormonal changes that manifest in serious physical symptoms.

[For more on this story by Claudia Rowe, go to https://www.seattletimes.com/e...ic-childhood-stress/]