Why Calmness Can Be Contagious

The powerful science behind co-regulation

Illustration: Jon Han

When the three-year-old Abby Perry was babysitting erupted into a tantrum about a toy he wanted to play with, Perry’s first instinct was to discipline him and remind him to share. “Then I thought, what would the point be?” she says. “This little boy was shrieking and unsettled, in a house he’d never visited, being cared for by a family he…