The next day when I was having lunch with Luisa and Gabriel in the school cafeteria, I told Luisa that I thought we’d solved Jade’s problem.

“What problem?” Gabriel asked, popping a grape into his mouth.

“Some people were laughing because she was a little taller than her partner,” I explained.

“If you can shrink her, that’d be real magic,” Gabriel said. “I told you my secret. Now you tell me yours.”

“Well, it’s still sort of yours, Gabe, so thank you for that,” I made a point to say. Then I described the skirt to him and Louisa, even sketching it out on a napkin. “It’s helping Jade dance like her old self,” I said, “but we can’t really be sure it works until next Saturday. So keep your fingers crossed.”

“Toes too,” Luisa said.

She wanted Jade to succeed just as much as I did. I realized then how much pressure Jade was under. Sometimes it seemed as if the whole performance depended on her doing well. If Jade could conquer her problems, somehow the rest of us knew that we could, too.

Please let the skirt work, I wished, trying to cross my toes inside my shoes.

During the week, Jade and I practiced at home every night, taking turns watching each other so that we could give each other advice. In her new practice skirt, Jade seemed as graceful as ever. As for me? I was willing to settle for not “bowling over” any furniture.

In spite of all of our practice, Jade grew quiet as we walked toward the theater on Saturday. I didn’t feel much like talking either—or even smiling. Maybe we were both too busy hoping that all of our hard work would pay off.

As we reached the stage door on the side of the HDC building, Jade reached for my arm to stop me. “Keep your mind on that toy top,” she said in a soft but firm voice. “Remember what Jackie said. Shake off any mistakes. Everything just bounces off you while you spin: sticks, stones, insults, jokes.” She swept her arm outward. “They just go flying off, right?”

“Right,” I said. “You keep that in mind, too.”

When we walked into Studio A and I saw Mr. Kosloff and Jackie Sanchez, I tried not to get nervous. Instead, I kept picturing that toy top whirling around and around.

Jade had worn a long, puffy coat to protect against the chilly morning air. As she took it off, Luisa asked, “Is this the skirt Isabelle designed? I like it.”

I glanced around, but no one else had noticed the skirt yet. And no one reacted to it during the party or battle scenes either. Without Paul dancing next to Jade, her skirt was just another rehearsal outfit.

But then came time for Jade to dance with Paul, her Nutcracker prince. I saw the ponytailed girl sitting next to the boy with glasses. They nudged each other as Jade danced a few early steps. When Paul finally stood up, I heard a giggle.

But as Jade and Paul began to dance, Jade’s footwork was perfect. She moved, spun, and leaped with her usual grace. And there was no laughter now. Instead, everyone grew still as they watched her. Jackie Sanchez leaned over and whispered something to Mr. Kosloff, and he nodded at Jade. I felt warm, thinking that my skirt had helped her a little bit.

When Act One ended, Renata stood next to me and sighed. “I wish I were you so I could watch Jade dance all the time,” she said dreamily.

“I’ll tell her that,” I said, wishing Renata would just go away.

Renata, though, stuck to me like a leech. “But maybe I don’t want to switch places with you after all,” she said, her tone changing. “I mean, who wants to keep being reminded that you’ll never be as good as your sister?”

I didn’t need Renata to tell me what I already knew. I already compared myself too often to my sister.

Don’t let her get to you, I told myself. Shake her words right off.

“Excuse me,” I said, keeping my voice steady, “but I’d like to get ready for our routine now.”

Renata smirked, but she left me alone.

Mr. Kosloff had been busy talking with Jackie and dictating notes to Bettina. But now he stood up to announce, “Let’s take a ten-minute break.” Then he crooked his finger at my sister. When Jade came over, I heard him ask, “Where did you get that skirt, Jade?”

“Isabelle designed it, and my family made it,” Jade said proudly, turning to smile at me.

Mr. Kosloff had my sister turn around a couple of times slowly so that he could study the skirt from different angles. Folding his arms, he paused thoughtfully, and then he waved me over, too. “Nice job with the skirt, Isabelle,” he praised, and I felt a warm rush of pride in my chest. Then he pointed at the ceiling. “Jade, will you go upstairs to wardrobe and ask for Margie? Tell her I want her to adjust your costume so that it has chevrons, like your practice skirt.”

As Mr. Kosloff headed toward the door, Jade skipped over to my side and pulled me into a hug. “The skirt worked,” she said, her voice muffled by my shoulder. “Thank you, Isabelle.”

“It would just be an old practice skirt without your dancing,” I reminded her.

But Jade shrugged off my words. She pressed her cheek against mine. “It’s time for the toy top now,” she said encouragingly. “Just remember: arms in, and spin so fast, you hum.” She made a humming noise that I could feel—almost like Tutu purring.

Then Jade let me go so that I could begin visualizing the toys in the chest.

Most of the other dancers left the studio during the break, but some of my castmates stayed behind, like me. They took small half steps, their eyes staring off into the distance while they imagined their routines. Ms. Ferri leaned against the wall, her arms folded as she kept an eye on all of us.

I felt my cheek where Jade had touched me and thought about her humming. I was a top, perfectly balanced as I spun. The spinning was my armor. Things bounced off. Nothing stuck. Not even Renata’s words.

When Jade came back in with everyone else, Ms. Ferri took her place at the center of the floor and reached her arms like a mother hen so that her chicks could take shelter beneath them. I headed over with the other dancers and found my starting position.

At the first note of music, Ms. Ferri lifted and lowered her feet as she softly began to keep count: “One. Two. Three. Four. And five.”

We began to move across the room like that giant crab. I tried not to think about how awkward and uncomfortable it was to be crouched down like this. Instead, I thought of how good it had felt to help my sister.

When we finally stopped, I scrunched down even lower and slipped away from under the imaginary skirt. I straightened and sprang upward, like Jack from his box. Lifting my head, I stretched my arms and legs outward as far as I could into a jeté. My landing was perfect.

As I neared Emilio, he began to stretch out his arms, and in my mind, I gave the toy top a twirl. I began my pirouette, arms in close and all my weight on one foot. Then I remembered Jade humming. That would be the sound of the top spinning. I was a perfectly balanced toy.

As I circled away, I glimpsed Emilio’s hands clutching at empty air. I was too fast. No one could catch me—not Agnes, not Luisa, not anyone. Not even Renata.

I danced back to Ms. Ferri. The others trailed behind me, but I would always be one step ahead of them.

I ducked down as if back under that imaginary skirt, moving around Ms. Ferri to make room for the others until she was surrounded.

She began moving her feet silently.

One. Two. Three. Four.

And then we were moving offstage.

When the piano music had finished, Luisa was the first to stand up. “That was perfect!” she said, giving me a hug.

It had felt perfect—well, almost perfect.

“You’re doing great, Isabelle. Just remember to smile,” Ms. Ferri pointed out. “Feel the joy.”

It was easy to smile now, because I knew that I had danced well and made no mistakes. I knew that I would be the Gingerbread Girl, not Renata.

But could I repeat that performance? And could I really pull it off before a live audience? I hope, I hope, I hope…I wished, still humming a little like that spinning toy top as I stepped off the dance floor.