One day in 2011, Kim Brooks made the fateful decision to run an errand at Target.

Not many horror stories start out that way — or do they? In "Small Animals: Parenthood in the Age of Fear," Brooks shows how parents' seemingly mundane decisions can lead to disastrous consequences, more often than you might think.

At the Target in the safe middle-class suburb where she grew up, Brooks' 4-year-old son whined to stay in the car playing on an iPad. Brooks cracked the windows, locked the doors, dashed inside for one item, ran outside —

And her son had been kidnapped?

Nah. That hardly ever happens.

Brooks' nightmare was a legal one. Someone had seen the boy alone in the car and called 911. Brooks faced criminal charges. What seemed, at worst, a momentary lapse in judgment held consequences that potentially could include losing her children.

“Small Animals,” by Kim Brooks

Spoiler alert: She doesn't. Her case dragged on for two years before she was sentenced to community service and parenting classes. Meanwhile, she was tormented by fear, embarrassment and shame.

Brooks is one of those ultra-conscientious mothers who strive, mostly successfully, to do everything right, based on "expert" advice and social expectations. Now she had begun to question her parenting competence.

But then she started wondering. Why should raising children seem fraught with constant peril? Why was she demonized for something her own parents wouldn't have thought twice about doing? Why were mothers "convinced that every single infinitesimal decision they made regarding their babies would determine whether it became secretary of state or a toothless meth head"?

In 2015, Brooks learned, traffic accidents injured 487 kids and killed three — every day. Meanwhile, statistically speaking, it would take 750,000 years for a child left alone in public to be snatched by a stranger. Although transporting children in cars is clearly far more dangerous, nobody questions that.

Consulting experts, authors and other mothers, Brooks uncovers some explanations for overblown parenting worries, including parents' perceptions of what they can control, their horror at rare but headline-making tragedies, and their sense of being judged by other parents.

She discovers that plenty of other parents have faced legal ordeals similar to hers. And that the system tends to treat poor parents and parents of color more harshly than it did Brooks, an educated, middle-class, white writer who could afford a lawyer.

My one frustration is that Brooks underemphasizes the fact that it's mostly mothers worrying about this stuff. She tends to refer to "parents" and "mothers" interchangeably, as if dads shared these burdens equally. Yet Brooks takes responsibility for providing most of the hypervigilance.

Her husband pops into the story only occasionally, mainly to wonder what all this perfect-parenting fuss is about.

Katy Read is a writer at the Star Tribune • 612-673-4583

Small Animals: Parenthood in the Age of Fear
By: Kim Brooks.
Publisher: Flatiron Books, 242 pages, $26.99.