Over the years, we have hit milestones with the regularity of the thump of a flat tire. Thump… thump… thump…. At first, it’s kind of reassuring to know that your child is hitting all the important milestones. But recently, it seems the car is speeding up and the milestones thump by faster and faster—at an alarming rate of speed, really. And this week, my daughter completed—and submitted—her first college application. Breathe.

These monumental occasions always give me pause and compel me to take a quick (or leisurely) inventory of the years that have come and gone. This most recent milestone hints at the small amount of time I have before she is off and testing her wings.

The early years of single parenthood are still vividly etched in my memory. I spent the days looking in the rearview mirror, counting heads in the backseat of the car. As the one parent of three very small children—all under five—I was always afraid that in my sleep-deprived state, I would leave one behind. Maybe one slipped by me somehow, and was still hiding in a store in the mall. Perhaps someone went to use the potty and was in the bathroom finishing up, or worse, didn’t get in the car and was standing in the driveway in a puddle of tears wondering why I left without him/her. In those early years, that fear never fully dissipated.

I blinked and we were in a new house in a new neighborhood with new friends and a new school. Little hands reached for mine with regularity. A hand to hold; a hand to help; a hand to lead the way. Those were days of constant attention and discovery and learning. There were toys and games and books and building and dancing and crafts. LOTS of crafts.

And then I blinked.

And the day came when they were all in school, mornings first and then full days. The school bus rumbled up the hill in the morning and swallowed them up. I would watch as the bus drove off up the road and out of sight before I ran home to switch to “adult” mode and be on my way to work. In the early days, I was home from work for 3:15, always needing to beat the bus to meet the kids so they were supervised and transported to the activity of the day. Always rushing so I wouldn’t be late.

Until I blinked.

The kids were able to ride the bus to their activities. My work hours increased, and an after school sitter took on some of my role. Extra keys were made and cell phones purchased and the kids further shaped their identities as they took their first tentative steps toward independence.

I blinked again, and now they are nearly through high school. They will be out on their own soon, with jobs and lives that take them all in different directions. That doesn’t mean my job is done. A mother’s work is never done, is it?

Just don’t blink.