The first time I went baby-sitting, my mother told me her secret weapon for getting babies to sleep.

I didn’t even realize she’d been using it on me all of those years, but now that the curtain was lifted, I saw the genius in her technique. When I had a hard time settling down as a child, my mom would come and place her thumb and forefinger in the middle of my forehead, then spread her fingers wide, stroking my eyebrows. I loved it. I felt completely relaxed and I fell asleep every time.

The cleverness of her system was that eyes naturally want to close when something approaches them, and we unwittingly hold stress in our foreheads. She took care of the stress and the difficulty of closing one’s eyes with one movement. And the magic trick worked for me, too. I considered myself quite an able baby sitter — I got the kids to sleep, every time, and then I went and did the dishes.

Studies show that touch can have a powerful impact on the human body. The first moments I held my children with skin-to-skin contact are some of the strongest memories I have of those otherwise sleep-deprived and hazy times. In those moments, I looked down at their tiny little heads, and I was overwhelmed with a fiercely protective desire to warm them, and love them, and let them know that they are not alone in this world.

In a 2015 article from The New Yorker called “The Power of Touch,” writer Maria Konnikova tells about the differences researchers found in Romanian babies who were raised in overcrowded orphanages with essentially no human touch compared with those who received higher-quality care. According to Konnikova, one researcher found that, “Even short bursts of touch — as little as 15 minutes in the evening — not only enhance growth and weight gain in children, but also lead to emotional, physical and cognitive improvements in adults.”

I thought about the power of touch last night, at the end of a rough day for my 7-year-old son. He’s a middle child, and most of his angst comes from not knowing where he fits in in this world. He wants to play with his older sister, but his overexuberance often makes her mad, and he thinks he’s too mature to play with his younger brother.

I scratched his back as he laid on his side and said he was sorry. “What for?” I asked him.

“For calling you a ‘meanie mom’ and saying all the bad names I could think of,” he said.

“It’s OK, buddy,” I said. All of his ferociousness from earlier that afternoon when I pulled him out of the pool because he wouldn’t stop fighting with his sister melted away as he asked me to scratch his head. It was almost like pushing a release button in his brain: his body relaxed, the stress went away, he was calm, all from a simple touch.

“Touch itself appears to stimulate our bodies to react in very specific ways,” Konnikova says in her article. “The more we learn about touch, the more we realize just how central it is in all aspects of our lives — from womb into old age. It’s no surprise that a single touch can affect us in multiple, powerful ways.”

That moment with my son made me think of those nights when I was younger and full of energy, unable to close my eyes, unable to settle down and sleep. The more I tried, the more agitated I became, and then my mother stroked my eyebrows and I could sleep.

It made me think of that powerful feeling I had when he was a newborn, resting his head on my chest, his tiny back rising and falling with each of his wispy breaths. He was just a little thing then. He didn’t know he had siblings. He didn’t even know he had a mother.

All he knew was that he was warm. And I was besotted. Seven years later, he doesn’t remember that moment, but I do. And in this hard and heavy world, he is not alone.