Anxiety is one of the most common childhood mental disorders. About 7 percent of children suffer from it at any given time, with nearly 1 in 3 adolescents experiencing it sometime during their teen years. For an anxious child, seemingly normal activities can be hard. Worried kids have trouble adjusting to school, making friends, and learning. They can feel inhibited and may avoid challenges by running away or retreating into themselves. While parents may feel desperate to help, their approaches can backfire. For example, trying to talk kids out of their feelings or keep them away from anxiety-producing situations may inadvertently make the anxiety worse. To help anxious kids, clinicians have developed treatments, such as cognitive-behavioral therapy, to alleviate symptoms. But the treatments can be cumbersome and expensive, and they don’t always work. Anxiety in kids as young as preschool-aged can be a sign of future trouble—a precursor to later disorders such …