THERE'S A BOY IN HERE by Judy Barron and Sean Barron (Simon & Schuster: $20; 262 pp.) The Barron household should have been home, sweet home, when young Judy Barron and her husband welcomed their first child. It was, instead, a house of horrors. Sean's relatives might have silenced his mother's harried complaints with comments about how boys are just unruly and difficult, but she knew he was much worse than that: He was prone to repetitive behavior from which he would not be distracted, he did not speak as well as other children his age, and the slightest thing--an unasked for glass of water in a restaurant--could send him into an uncontrollable rage. This book is the story of the Barrons' descent, as Sean's autism threatened the family's sanity, and their rebirth, as he crawled far enough out of his private hell to lead a semblance of a normal life. It is also the story, sadly, of a dismissive medical Establishment, whose snap diagnoses and pharmaceutical solutions alienated the Barrons early on, and of parents, since Judy Barron has the good grace to be frank, who all too often succumbed to their anger and frustration. Her son's reminiscences are eerie and frightening, versions of reality as only he perceived it. If his mother's style is less affecting, it is perhaps understandable; underlying her story is a vast, almost incomprehensible exhaustion.