It feels like the beginning of goodbye.

Oh, sure, my son is still a little boy, but not for long. Not really. His little-boy status is about change.

For his entire life, my son and I have spent more time together than apart.

He’s eaten lunch with me every day at our well-loved kitchen island.

Afternoons have always involved nap time stories and snuggles—at first in a weathered rocking chair and more recently in his big but still little boy bed.

He’s always kept me company in the car while waiting for the bell to ring at his big sister’s school.

But this year? We’re saying goodbye to the routines we’ve known his whole life. And he’ll start a whole new routine that doesn’t much involve me.

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I knew this day was coming, but with how slowly so many days seem to drip by, I didn’t expect for it to arrive in such a rush.

Kindergarten.

The first day of this latest milestone is upon us. The preschool days are over. No more half-days and lunches with mom. No more afternoon snuggles and mommy-son storytime.

This year, my son will begin every-day, all-day school. And though he’ll walk through those school doors still a little boy, it feels like the beginning of goodbye because I know how these early elementary years tend to edge out a child’s littleness. It feels like one big step—between a whole lot of little steps—away from me.

I’ll send him off to kindergarten as a boy who still holds my hand in the school parking lot, wearing shoes tied by me, and carrying a backpack that’s still a little too big for his little boy body.

I’ll remind myself that we’re just at the beginning of these full-time school years, that he still needs me, and that there’s still LOTS of time. But thinking about time tends to dizzy me with panic.

Because when these years are done? He’ll come out of those school doors a man.

And if I’ve learned anything about raising kids, it’s that days can feel like an eternity, but years tend to fly by in an instant.

The thing about little boys is that they grow into big men. And I can’t keep up with the pace of my little boy’s growth.

The start of kindergarten means we’re quickly approaching the end of the little boy years.

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But we’re also starting the journey from boyhood to manhood, and while I’m mourning all that we’re leaving behind, I’m excited to see what’s up ahead.

I’m going to miss the little boy my son is, the little boy he’s been.

But I’m excited to meet the man he’s going to become—and all the versions of him that will emerge between now and then.

Every day at pre-school pickup, he came barreling out the doors, launching himself off the concrete and into my arms—half-boy, half-rocket.

And next? He’ll be a grown man launching from the classroom and into a world full of possibility. Without me.

Or at least that’s how it feels.

So, I’m going to savor these days and probably grieve them a little too. But I’m looking forward to seeing where this kindergartner-soon-to-be-man lands.