There is hardly a more concentrated dose of the joy of motherhood than when my preschooler runs to me after class, arms outstretched and joyfully shrieking, “Mommy!” No matter how big of a disaster we were getting out the door that morning, or how many questions he flings at me on the car ride home, or how strongly he protests dinner that night, I can always hold up the 3pm pick-up moment as the “it’s all worth it” consolation prize of this phase of motherhood.

It’s getting harder, though. He is five years old now, starting kindergarten in the fall. When he runs to me and jumps up into my arms, I have to brace myself for his weight. Even then, with my knees bent and my body readied, when I first catch him under his arms I have to pause for a second. I hold him a couple inches off the ground for a beat while his inertia makes his legs swing between mine. Then, as he swings backwards a bit, I use his momentum to hoist his body all the way up into my arms. He clings to me like a tree frog for a tiny, brief moment and I bury my nose in his hair and for a milisecond he feels like a newborn and I swear I’ll never put him down.

His newborn days are long gone, though, and I know what’s coming next: I’m not going to be able to pick him up like this for much longer. I’ve heard other moms talk about the last time they really picked their kid up, how they didn’t even realize it was the last time until weeks or months later. How you pick them up less and less as they get older, as they need you less, as your arms grow increasingly full of other duties and projects and babies. It feels a bit like a race against time; which will come first— will he become too cool to want to jump into my arms, or will he get so heavy that I can’t lift him? Either one will break my heart.

I haven’t been as prone to the “stop growing up” sentiment that a lot of my friends express about the bittersweet feeling that accompanies so many of our kids’ big milestones. The first tooth got me — knowing that gummy baby smile was gone forever felt devastatingly final. The first steps, though, and the first foods, and the first trip to the movie theater, those all came and went without much fanfare for me. These toddler years have been trying, and I’ve often looked forward to the next phase with hopes for a bit of respite. First steps meant the end of the crawling phase that exposed just how dirty the floors are. First foods meant getting closer to sitting down and eating as a family instead of taking shifts while someone fed the baby. The first movie was a beacon of all the shared activities I hope lie ahead for us as my boys outgrow Daniel Tiger and the accompanying songs I’ll be happy to have out of my head forever. I have welcomed those milestones wholeheartedly.

The knowledge of this next one, though, the threat that the last time I’ll pick him up is just around the corner… it feels different. It feels bigger. The final buzzer on the end of his babyhood, which to the untrained eye was over a long time ago. I’ve managed to hold onto it, though, in that smell of his hair when he wraps his arms around my neck. It is there that I can forgive his toddler tantrums and his preschooler arguing and his repetitive questions and terrible table manners. It is there that I renew my vows of patience and selflessness and matchbox cars. When he’s in my arms, he is still my baby and I’m his rock and everything is so simple.

What will happen when we lose that moment? When he opts to just wave at me rather than run to me, or when he is so big that I can no longer cheat with momentum to lift him up? What will happen when I can no longer find his babyhood, buried deep in the smell of his hair where only a mother would know to look?

I am surprised at how sad it makes me. For all the times I’ve looked at the clock and tried to will it to be his bed time, for all the 5pm S.O.S. text messages I’ve sent to my husband and all the time outs where I needed to calm down as much as my son did — I am caught entirely off guard to feel so suddenly attached to this phase of life that has often been so challenging.

It’s in that sadness where I see that my son isn’t the only one growing and changing and leaving one phase to start a new one. I’m changing, too. And maybe it’s not just the loss of his babyhood that weighs heavy in my heart, but the reminder that time is constantly moving forward and with each big milestone I hear the question, “What do you have to show for this?”

As I do the work of raising my kids, the work raises me, too. While my son sheds his last wisp of babyhood, I am catapulted into a new phase of life right alongside him. No longer a new mom. No longer naive about doing it perfectly or having it all or doing X to reliably produce Y. I’ve fought those battles. I’ve left parts of myself—and found parts of myself—on those battlefields. Amidst his first tooth and first steps and first peanut butter sandwich, I’ve had my own milestones along the way.

For now, I can still cheat my way into his tree frog embrace. I can brace myself and use the momentum of the upswing. I can hold him tightly with one foot where we’ve been and one foot in uncharted territory and wonder who exactly we’ll become when we get there. 

Written by Anna Quinlan.