In the back of my closet is a small cardboard chest with brass handles and latches that has followed me to every new address; it’s the first thing I find a place for as the moving truck pulls away. An old sticker on the bottom says it was purchased at Ross for $26.99. The only remaining contents are three wrapped presents marked in my mother’s tidy cursive: “Engagement,” “Wedding” and “First Baby.”

My mother, who put her business degree to use running a small nutritional beverage company with my father in Santa Rosa, Calif., while raising my older brother and me, was always prepared. By day she made marketing slogans, distribution strategies, five-year plans. By night: bubble baths, pillow forts, bedtime stories.

She and I had the same February birthday. Each year my parents arranged elaborate parties. She once spent a week making a school of origami fish to swim through tissue paper seaweed across the ceiling of our dining room.

When I was 3, she learned she had advanced breast cancer and immediately began to prepare by researching every available treatment: conventional, alternative, Hail Mary. She flooded her body with chemotherapy and carrot juice.

Each day, she would sit for hours at our long oval dining table, her straight dark hair tied back, surrounded by piles of paper, studying dense, technical paragraphs.

“Medical research,” my father said as he shepherded me from the room.

She was always looking for a way to survive.

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When I was 7, the materials on the dining table began to change. Wrapping paper and ribbons took the place of her highlighted pages as her arms worked busily under the dark fuzz of her shorn head. Scissors swished through gift wrap. Paper creased under her fingers. Ribbon cut to length with one snip. Knots came together with a tiny creak. Swish, crease, snip, creak.

She had begun assembling two gift boxes: one for my brother and one for me.

There was a rhythm in the room. She bent closer and closer to write the labels as her vision began to fail, a result of the cancer having spread to her brain.

Inside, she packed presents and letters for the milestones of our lives she would miss — driver’s license, graduation and every birthday until the age of 30. When the boxes were full, my father carried them up to our rooms. She died 10 days before our shared birthday.

That morning, when I turned 12 and she would have turned 49, I woke up early. The box sat three steps from the foot of my bed. Just as my mother had shown me, I lifted the latches and opened it.

Neat rows of brightly wrapped presents glowed like the spring tulips that were just coming up in the front yard. I opened the package marked “12th Birthday” and found a little ring with an amethyst at its center. A white card curling around the present read: “I always wanted a birthstone ring when I was a little girl. Your Granny finally bought me one and I loved it more than I can say. I hope you like it, too. Happy birthday, darling girl! Love, your Mommy.”

I slid the ring on and traced her writing with my fingertip. Her words, written to bridge the gap between us, cut through space and time.

When I got my first period and couldn’t bring myself to talk to my father about it, a four-page letter from my mother (marked “First Period”) laid out practical advice: “Take time to make friends with yourself. Take time to learn what interests you, what your opinions and feelings are, find your own sense of the world and which values you hold most dear.”

As I read, I wanted to fall through the white, lightly textured page and into her arms.

“Please try not to lose yourself,” it continued. “These are challenging years. Call on me for help when you feel confused.”

On the morning of my high school graduation, a strand of pearls made a sound like a maraca as I drew them from the box. Her note read: “There seemed to be a tradition in my family that when girls graduated from high school, they received a string of pearls. Well, my string of pearls never arrived.”

That’s because my mother, bound for adventure, skipped her senior year, and bought herself these pearls when she finished business school. She wanted me to know there was more than one path to walk through the world, and that I deserved to be celebrated. I wore the pearls that afternoon as I crossed the football field to accept my diploma.

Year after year, my mother traveled forward in time to meet me, always in the guise of a little package with a pink ribbon and a little white notecard: “Happy 15th!” “Happy 16th!” “Congratulations on your driver’s license!” “You’re a college girl!” “Happy 21st!” “Happy birthday, darling girl! Love, your Mommy.”

Each time I opened the box, I could, for the briefest moment, inhabit a shared reality, something she imagined for us many years ago. It was like a half-remembered scent, the first notes of a familiar song, each time, a tiny glimpse of her.

When I was a child, opening the next package felt like a treasure hunt. As I grew older, it began to feel like something far more fundamental, like air or community, something like prayer. Her messages met me like guideposts in a dark forest; if her words couldn’t point the way, at least they offered the comfort of knowing someone had been there before.

A decade after I lost my mother, my father followed suddenly. She had spent years preparing her exit, but with him I blinked, and he was gone. The morning of his memorial, the box stared back at me with nothing to say. There was no letter for this.

I tried to conjure her voice but couldn’t. My father left no clues or letters. The only parenting I would have, from 22 on, was in the box.

When I hit 30, the nearly empty box sat in my Brooklyn apartment, clashing with the furniture. Only those three packages remained: Engagement, Wedding, First Baby. They sat in their shiny cardboard and pink ribbon, expectant, waiting.

The problem was, I didn’t know if any of those things would happen. I didn’t know if I would choose them.

I had been living with someone for three years. I didn’t know if I ever wanted to get married, but I was in a committed, loving relationship, and whatever advice my mother had about committed, loving relationships, I wanted it. Now.

I felt 12 again, and rebellious, as I pulled out the thick envelope marked “Engagement.” My fingertips felt cold as I opened it.

It read: “My dearest little girl, of course you aren’t so little anymore as you read this but, you are little as I write. You are only 7 and I am facing the terrible sadness that you will be growing up without me.”

With the smooth pages crinkled in my grip, I found her hopes for what my marriage might look like.

“A true marriage is a marriage of what is most sacred in both of you. One must have an ease about both giving and receiving, a capacity for forgiveness for oneself as well as for the other, a personal sense of balance that is not dependent on the balance of the other, a kind of loving detachment.”

I didn’t know if I was capable of loving detachment. There was no detachment in the love that made the box, and no detachment in the love that opened it.

“I’m so sorry to be leaving you. Please forgive me. I know a box of letters and tokens can’t begin to take my place, but I wanted so badly to do something to ease your way through the future. Love, your Mommy.”

For 20 years I have pulled mothering from the box, but I don’t know if the next 20 will include the milestones she planned for me. I often wish I could lift the latches, jump inside and ask her which path I should walk and how I will recognize it. I want to ask if the life I’m carving for myself looks anything like she would have hoped. But I know this time travel only works one way.

After I read the engagement letter, I put it back with its unopened package and closed the box. Those three final secrets will remain secrets, for now. Maybe I’ll open them tomorrow, or in 10 years, or 20.

There’s comfort in knowing there’s a little left in the box. My mother’s gifts, her letters, are a constant reminder that I have already been given what every child, what every human, needs: I have been fiercely, extravagantly, wildly loved.

Genevieve Kingston, a writer and actor in Brooklyn, is working on a memoir.

Modern Love can be reached at modernlove@nytimes.com.

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