As a primary care pediatrician, I spend most of my days talking about things that are hard for families. Parents ask what to do when their child won't poop on the potty. Or how to get their baby to sleep longer or how to get their teenager to wake up earlier. They ask how to get their child to sit in the car seat or what to do when they get car sick on long rides. And over the years I have developed a list of problem-solving strategies to help. But the one that has recently become my...