I embraced minimalism. There was always a bulky sweater left behind, always a tough decision in favor of navy or black but never both. My suitcase was light, its top as concave as a starlet’s pelvis. I was coming home from the moment I walked out the door.

Sarah sat on our bed to watch me pack, the first time, silently considering the unfriendly way that time and space conspired to create separation. She tallied every sock and belt, and then she got up and disappeared down the hallway to her own room. Moments later she returned and held out a small stuffed bear to me. She always has a ramrod spine when important matters are on the line, and I could tell from the way she stood that we had entered a realm that had nothing to do with whether I’d packed enough underwear.

“Here,” she said. “You can take her with you.”

In a spasm of responsible parenting, we had bought three identical oatmeal-colored bears with lavender ribbons around their necks, all because someone with credentials had mentioned that it was very bad for little children to lose a favorite stuffed animal. Sarah was fairly tidy about her favorites, though, so we had a surplus of this particular model, which turned out to have an unexpected advantage. We might be separated by an entire country, but we each had an identical bear, and that link was as strong as a steel span between us.

I took the bear. While a more rational mom might have left it in the suitcase, I believed as devoutly as Sarah did in the magical ability of bears to erase distance, if properly displayed. It sat on my pillow for the duration of the trip.

As she got bigger, the tokens changed: I traveled to New York with a good-sized one-eyed patchwork horse, with a crib blanket that Sarah was proud no longer to need now that she had a big-girl’s bed, with a shredded baby blanket that we had to fold inside a plastic bag lest it shed flannel lint all over my dark suit. On one trip, I took the largest doll Sarah owned, a by now rather blowsy platinum blonde with one sagging eyelid, dressed in a shiny white polyester wedding gown.

In return, I made a book out of colored construction paper each time I went away: “Sarah’s Book about Mommy’s Trip,” “The Story of Sarah and the Magic Heart,” titles like that, illustrated with plump airplanes that smiled, talking horses, and floating hearts. If it seems slightly frantic in retrospect, it seemed as essential as air at the time. We had been a family for such a short time; the way it felt was so new, and as fragile as it was overwhelming. We had to keep love right in front of our eyes at all times. Evidence reassured us.

The insidious thing about Sarah leaving is how subtly the balance tipped—how we endorsed the inevitable without realizing it. We taught her to flee, didn’t we: Her first piece of luggage, the diaper bag, got her not just to the park but to the train station, to the airport, to places no self-respecting baby would ever go unless her parents packed her supplies and took her there. We encouraged her to take a look around, and once she’s gone I will have lots of time to wonder why we didn’t stick to the neighborhood, where we might have successfully raised a kid who never wanted to be more than a zip code away.

By the time she started first grade she had a passport and her own little flowered knapsack, into which she packed the things that mattered to her when we went on a vacation: eight or nine stuffed animals and a pad and colored pencils for drawing. On one trip she listened to Charlotte’s Web while the grown-ups talked, our separation from her punctuated by the occasional random chuckle or sigh from the backseat of the rented car. She might not have had any idea of what to pack to survive on her own, but she had learned that going places was fun, and that she could find ways to entertain herself while the adults droned on about whether we should’ve taken that last left turn and the likelihood that we were lost.

Once she got to middle school, she acquired a series of backpacks of increasing and worrisome heft. A tiny friend who hoisted her pack onto her shoulders but forgot to lean forward to compensate fell right back on top of it, and lay there for a minute, helpless, her arms and legs wriggling like a beetle flipped onto its carapace. The other girls had to grab her arms and help her up—and yet we could not persuade Sarah to leave the history book in her locker until she needed it at the end of the day, or to leave the math book home if she didn’t have math class. Those literally weighty tomes were the keys to the kingdom, though we didn’t comprehend it at the time: Learn all this stuff, fill out a bunch of forms, graduate, and presto, you get to go to college.

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