The last few days, I’ve been thinking about what impacts kids’ lives. This line of thinking was inspired by these seven words, which no parent wants to hear: “Dad, I was hit by a car.”

It was a sunny, warm Thursday afternoon. My 15-year-old son, Ian, was biking home from school. It’s a mile-and-a-half ride that he does frequently. But this time, around the corner from home, he was crossing a driveway, and at the same time a woman was driving out of it. Ian thought she saw him, so he kept going. Unaware of him, she put her foot on the accelerator and hit him. He flew onto the hood of her car, then hit the pavement.

He told me later that those few seconds slowed to a crawl, like a series of frames in the movie playing in his mind. In the instant before impact, he knew she was going to hit him. In the split-second after that, he lost his balance. Felt himself hit the hood. Was aware that he was airborne, tumbling. Saw the pavement rush up at him. Put his arm out to break the impact. And then he was on the ground, dazed and scraped and bloody. The driver—a woman of about 70—helped him off the street and onto the grass, where he called his mother and me. Luckily, I was home from work that day.

I ran from my house, five minutes from where Ian was, and on the way I saw flashing police lights that I knew were heading for him. When I arrived, I threw my car into park, jumped out, and ran. I knew Ian was basically okay—after all, he’d called me—but I wanted to be next to him. I had to see him. Touch him. Hear him. His mother was already there, along with half a dozen police officers, paramedics, an ambulance, the woman who’d hit him, and a bystander who’d called 911.

“Are you his father?”

“Yes.”

I knelt in the grass next to him. There was a nasty scrape on his forehead and another on his arm. The blood was fresh, sparkling in the sunshine. Ian’s bike was twenty feet away, in the grass, the handlebars twisted 90 degrees.

On the way to the hospital, in the ambulance, Ian Snapchatted his friends. Word spread fast and concern poured in. I found myself grateful that Ian and his brother Jeremy go to the climbing gym so often. They know how to control their bodies. They know how to fall.

As a dad, I spend a lot of time in the moment, making what feel like snap decisions about steering my kids this way or that. But at the same time, I also look ahead to what my kids’ lives might eventually look like. Ian wants to make movies, and even at 15 he’s already writing scripts and directing short films. He meets these challenges like any filmmaker, with dedication, intelligence, and creativity.

When I look ahead, I see him on a set, at the center of an immense production, in charge of a battalion of technicians and actors. I see him on the stage at the Oscars. I see Ian as he might be, and I see him as he is. I see his commitment to writing, to fleshing out ideas, and to performing in his high school’s musicals, which he wanted to do originally because he was curious about how it would feel to be directed. I see his commitment to his friends. I see a young man who puts every last iota of effort into everything he does. I see a boy who cares, who knows that caring and effort and kindness matter, and who understands that if it’s worth doing, it’s worth doing well.

I also see Ian with his family, with the kids he’ll have, enjoying quiet moments that will give him a lifetime of pleasure and memories. I also see that, like me, he will worry about all the things beyond his reach. One day he’ll realize, as I have, that there are things he simply can’t control, things he can’t direct.

Like a woman driving into him.

The things that impact our lives can be such small things. Every day, we all survive what will, a moment from now, be the past. But what about the future? The future is at the mercy, really, of everything we can’t control. Every other driver. Every other person. Every other everything.

After Ellen and I got pregnant, I used to talk about the wonder of tiny things. How, if the circumstances had been even slightly different, a different sperm would have reached the egg, and we’d have a different child now. Such small things. Tiny differences. It used to fascinate me, but now it frightens me deeply to know that massive impact can be caused by even the smallest incremental difference.

If the driver last Thursday had been going only one or two miles per hour faster, Ian might be in a very different place today. We all might. When my mind goes there, I imagine all the lost moments that haven’t even been moments yet. Ian’s work. His family. His joys and sorrows. His dreams. His reality.

When I look at my son, I feel such pride. I see how strong he is—and also how fragile. I see the impact he’s already having on the world, and I see the impact the world has on him.

—Tony Buchsbaum