I crossed the aisle today.

You know, the one that separates the toddler sizes from the big kid sizes.

If you’re shrugging your shoulders and saying, “So what?”  it’s probably because you haven’t done it yet.

The other morning our four-year-old was standing in the kitchen when I noticed how short his 5T pajamas were getting on his tall frame. It was obvious he needed the next size up, so I made a mental note to grab some for him the next time I went to Target. Not a big deal.

Except it WAS a big deal to this mama’s heart.

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I was standing right smack dab in the middle of the toddler section, between the Cat & Jack and Carter’s when it hit me that there was no such thing as 6T.

Because once a kid is big enough to be in 6T, he’s actually ready to move on up to boy sizes.

Not baby. Not toddler. But boy. Like, KID boy.

Across the aisle.

I realized in that moment I’ve been living in denial.

I see my boy growing up before my eyes. I’ve noticed the edges of his face becoming less round and more mature. I’ve heard the witty things he says. I’ve noticed the way he pours his own cereal and makes his own bed. I’ve listened as he tells me more and more often, “No thanks, Mom. I don’t need help this time.”

I’ve had a front-row seat to his metamorphosis, but I haven’t accepted it—not really.

Because in my mind, he’s still a baby. That sweet, smiley, precious little baby—the first one we ever brought home from the hospital.

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My heart hasn’t been ready to admit that now he’s a boy who will be starting school in the blink of an eye. A boy who is officially outgrowing the remnants of toddlerhood. A boy whose height apparently requires his mama to make her first trips across the aisle.

As I stepped foot into the big boy section, my heart physically ached at the reminder of passing time.

I felt a spark of hope when I saw how big all of the clothes hanging on the racks were. They were HUGE—surely he wasn’t really big enough to wear those yet. Surely it wasn’t time.

I grabbed a pair of Spiderman pajamas and made my way to the checkout, hopeful we’d have to store them in the closet for a while until he grew into them.

On the drive home, I thought about newborn giggles and determined first steps and the way it sounded the first time he called me Mama.

Then I thought with pride about all the things he’s doing now. Playing basketball, learning to read, soaking up the world around him.

And last, I thought about all the things his future has in store.

And I smiled through teary eyes.

At home, his eyes lit up when I handed him the bag, and even though it was only 4:30 he ran off to his room to change. I watched him go and swallowed the lump in my throat.

He’s growing up, this beautiful first blessing of mine—but we’re both gonna be OK.

And those boy-sized Spiderman PJs?

They fit perfectly.