Every night for so many nights, it was the same. You started the process. You got them into the bathroom. You got them into bed. You read to them. Then they fell asleep.

And then one day, you didn’t. Or one day—if you’re still in it—you won’t. We know this is how it goes, but still it surprises us. Still, it seems like it will go on forever. Life seems stable, routine seems eternal and yet deep down we know it isn’t. We know…and constantly forget…that this cannot last.

In her beautiful book Papyrus, which is all about the history of books in the ancient world (it’s much more interesting than it sounds, we promise), Irene Vallejo reflects on the many nights her mother read to her. “My favorite thing to do while she told me stories,” Vallejo writes, “was to wiggle a dangling tooth with my finger, feel it detach from its root, come looser and looser, and when it finally fell out with a few salty strands of blood, gaze at it in the palm of my hand. My childhood was breaking apart, leaving gaps in my body and little white shards behind me. The time for listening to stories would soon be over, though I didn’t know it yet.”

One night will be the last night, just as one reading level leads to the next—the board books are left behind for big colorful children’s books to Harry Potter to the classics, just as it eventually leads to them reading on their own and inevitably to them moving out.

But here you are, today, acting like it’s not happening. Here you are acting like you have forever, like it will always be this way. Except this isn’t forever. This is right now. So be here for it. Show up for it. One day, you’ll miss this. One day, you’d do anything to get back to this.