When my son was not quite two and I was pregnant with my daughter, I had a client whose focus was building community awareness of the importance of early childhood development. As the hired PR help, I was the group’s first disciple. I read Ghosts from the Nursery and Neurons to Neighborhoods and countless research articles as part of my mission to share the gospel of how a child’s first years last a lifetime.

As a result, I worried obsessively about how much I’d done to screw up my son’s first 18 months. I raced out to buy developmentally appropriate books and toys. Once, when I picked him up from my mother’s house, I lectured her for sitting in the kitchen floor with him, playing with measuring cups and bowls of water instead of working with the slew of brain-stimulating gadgets I’d left for her. “Don’t you know, Mother? His first three years are the most important of his entire life! His brain is developing faster than it ever will!” My patient mother replied that she hoped those people at Princeton never found out that all I had as a child were measuring cups and bowls of water. She was a good mother.

For the next two years I remained certain that I’d made nothing but blunders, certain that my son’s wild mischief was a direct result of something I had or hadn’t done. When he was four and my daughter two, we sat in a room at the pediatrician’s office waiting for the doctor to come in for their annual check ups. When Chris, the doctor, walked into the room my son was trying to climb the inside of the window while my daughter was sitting at a table looking at a picture book.

“Please tell me this is classic boy-girl behavior difference,” I begged. “Maybe,” he replied, with a look of calm understanding. “Or maybe we just are who we are from the moment we pop out, some of us quiet and some a bit more energetic.”

It was several years before I began to consider that he might actually be right, that these little people I’d birthed might have been endowed with their own individual natures and that my job might be to coach them into being the best versions of themselves instead of steering them toward my idea of what they should be.

I wasn’t fully convinced, however, until this past weekend when I attended my 30th high school reunion. As I looked around at our gathering, in a series of split-second frames I saw us in third grade and fifth grade and eighth grade and 12th grade all at once. In that moment I recognized us now as the woman versions of our child selves, shaped by the years in between and yet entirely the same.

And at that moment I fully understood what my mother and my pediatrician had tried to help my stubborn, strong-willed, pig-headed self see: we are who we are. And if we’re lucky enough to be surrounded by people who love and accept and encourage the goodness and strengths that are in us to begin with, then maybe someday we can become the best versions of ourselves. It’s what my mother hoped for me. Really, she was a good mother.