Parents need to reassure kids repeatedly that they are safe because the images from traumatic events can be haunting. They should explain in concrete terms that police and teachers are working to keep schools safe and that what happened in Newtown, Conn., is a rare event.
That's how adults put things into perspective. They know that the odds are incredibly long that their child's school is going to have such an incident.
And yet, kids might not know that. They are especially prone to what's known as "thinking errors" after trauma, Howard said.
"They are especially prone to what we call magical thinking or associative logic, so [they think that] if it happened in a kindergarten classroom, it will happen in another kindergarten classroom," Howard said. "So parents need to monitor and correct kids' magical thinking."
Several professionals said the best comfort may not be verbal. Instead, as President Obama noted Friday, parental reassurance comes in many forms.
"This evening, Michelle and I will do what I know every parent in America will do, which is hug our children a little tighter, and we'll tell them that we love them," Obama said.
There is abundant research, Kazdin said, "from animal research to human research, to research with premature babies, that suggests that touch, the comforting, has strong biological effects on all facets of the organism -- managing stress, comforting. So it's not just a cliche of parenthood. It's wisdom through the ages that now has science behind it."
So when words fail, never underestimate the power of an embrace.