When Shannon Hyland-Tassava heard about Leiby Kletzky's murder Wednesday morning, she posted her reaction on Facebook.

"This is why it will never bother me to err on the more protective side with my kids if given the option," the Northfield psychologist, writer and mother of two wrote. "I don't care if it's statistically unlikely to happen; IT CAN HAPPEN. Horrifying."

Similar emotions echoed nationwide this week after news broke about the New York City 8-year-old who was murdered and dismembered after getting lost walking home alone from day camp. It's a case that embodies some of parents' worst terrors.

"Immediately I thought, I don't care who calls me overprotective; I'm going to walk my children to and from everything," Hyland-Tassava said in an interview. "Because I can't even bear hearing about things like this when they do happen."

Cases like Leiby's are extremely rare. A study by the U.S. Department of Justice counted 115 children abducted by strangers in 1999. Of those, less than half were killed or never found. Those numbers don't change much from year to year, said Nancy McBride, national safety director at the National Center for Missing and Exploited Children.

Those statistics should be reassuring, but some experts say it's the rarity of such stories -- along with the media attention they generate -- that makes them the stuff of parental nightmares.

"They stick out, they play and replay in parents' minds," said Hara Estroff Marano, author of "A Nation of Wimps: The High Cost of Invasive Parenting."

Despite major progress in children's health and safety, today's parents worry more than ever about protecting their offspring from harm, according to Peter Stearns, author of "Anxious Parents: A History of Modern Childrearing in America." In the past, "there was a greater sense that childhood carried some risks and there was not much to be done about it," he said. Now, "we don't like the idea of any risk."

Meanwhile, concepts of what represents real risk are distorted, said Lenore Skenazy, author of "Free Range Kids: Giving Our Children the Freedom We Had Without Going Nuts With Worry." She predicts that parents will focus on Leiby's case rather than on the millions of children who have walked alone with no problem, or on all of the children who die each year from less sensational causes.

When a friend e-mailed her to say that, after the Leiby killing, his wife no longer believes kids should be allowed to roam solo, "I wrote back, 'Well, I hope she never puts your 7-year-old in a car,'" said Skenazy, who became famous for letting her 9-year-old ride the New York subway alone. She pointed out that children are 25 times more likely to be killed in car crashes than murdered by strangers.

Kelli von Heydekampf, a mother of three in Edina who is a member of the Star Tribune Moms panel, tries to prepare her three children for taking "age-appropriate risks." Last year, she gave her then-12-year-old daughter permission to bike 3 miles to the community pool. But none of the girl's friends were allowed to join her, so she never went.

"There's no guarantee that nothing's ever going to happen, and that's the scary part," she said. "But it's my job as a parent to give them the skills they need to lead independent, productive lives."

Hyland-Tassava said that, as a psychologist, she fully understands all these arguments. Yet she is determined to safeguard her kids, even if it means overprotecting them.

"It's not necessarily a real rational emotional response," she acknowledged. "But how can you be rational when you hear about such a terrible, terrible, unspeakable tragedy?"

Katy Read • 612-673-4583