Little Disasters

By Sarah Vaughan. (Emily Bestner Books/Atria, 420 pages, $17.)

What would you do if one of your dear, trusted friends was suspected of harming her baby?

Liz, a pediatrician who went through birth classes with Jess, knows what a great mother she is to her two children. But when Jess shows up with little Betsy in the ER with life-threatening signs that point to child abuse, plus a questionable story as to how Betsy was hurt, suddenly friendship takes a back seat. Liz, as required by law, notifies authorities, and the nightmare begins.

The tragedy is even more complicated because the birth class where Liz's and Jess' families met also included two other husbands and wives with whom they've become fast friends. When Betsy's injuries come to light and Jess comes under suspicion, the couples fray in ways that betray confidences, loyalty and interpersonal ethics.

Sarah Vaughan, bestselling author of "Anatomy of a Scandal," employs searing emotions and soul-searching gymnastics as these couples try to justify or explain how this perfect mother could have cracked. Or did she?

Each of the mothers, and some of the dads, are forced to examine their own parenting weaknesses in ways that make them both turn on Jess and embrace her possible moment of breakdown.

It's a great, twisting mystery until the end, and it's worth staying up late a night or two to explore this complicated drama.