To all the moms who get a bit teary at the start of school. To the moms who view the new semester with a nostalgic heaviness. To the moms who see the sands of time slipping through an hourglass and mourn how quickly it passes—you are not alone. 

This time of year holds a certain weight; there’s a nostalgic heaviness as the start of school looms. These days remind us just how fleeting childhood is. They are a tangible reminder of the reality that our children won’t always be little. So we mourn the start of school with the knowledge that babies don’t keep. 

Related: I’m the mom who cried after dropping my kid off for their first day of kindergarten

We may look like we have it all together. We may paste a smile on our face and post the back-to-school photos and plan the after-school treat. But inside, we’re dying just a bit, overwhelmed by the emotions of the passage of time and the reality that life isn’t going to slow down. 

This is me every year. Maybe it’s you. My oldest is entering ninth grade, and I’m acutely aware of the fact that he only has four years left at home. Four precious years. I can freeze his smile with one click of my camera, but I can’t freeze time. It marches on and the school bell tolls to signal its passing. 

Related: This mama perfectly explains how time changes when you become a mother

Mothers across the world understand this ache—this tension of letting go while holding tight. There are moms sending their first-borns to kindergarten knowing a chapter has closed. There are moms sending their babies to college knowing a season has ended. There are moms everywhere in between mourning the passing of time. If this is you, I don’t have words of wisdom. I’m simply here to sit with you in the sadness.

Because this year, when you’re swallowing the lump in your throat and waving good-bye and counting down the minutes until pick up, you need to know that someone else feels it too. And friend, you’ll make it through. You’ll make it through this growing and this letting go, but right now, it’s OK to feel the tension of chapters closing and new ones beginning.

Related: I wasn’t prepared for the grief each milestone would bring

Because you are a mother giving roots and wings to a child learning to fly. It’s beautiful and brave and heartbreakingly hard, but you are not alone. You’re not the only one lingering after drop off. You’re not the only one trying to calm an anxious heart. You’re not the only one wiping away tears in the carpool line. You’re part of a sacred bond of moms who understand the tension of clinging tight while letting go. 

One day, we’ll look back and see the glorious sanctity of this process, but today is not that day. Today, letting go is hard. So for now, dear mama, go ahead and sit in the sadness. 

And know that I’ll sit here, too.