That evening the sky was clear and cool, the kind that tastes a little of winter even though winter has not come yet. Lily, Ziggy, Skye and Dash were in the garden, lying on an old blanket, playing at guessing the shapes of the clouds before the dark hid them away.

"That one looks like an elephant!" said Dash, laughing.

"And that one is a hat!" said Ziggy.

Lily said nothing. She looked up with her blue eyes, because she had seen something the others had not noticed: the moon was rising, big, round and silvery, and it lit up the whole garden with a milky light.

"Look at the moon," whispered Lily. "Tonight it is full, so full."

Just then, from far away, came a sound they knew well.

"CHOO CHOO!"

Between the trees popped two little yellow lights, and then all of him: Toby the Magic Train, with his smoke that smelled of sugar. He stopped by the hedge, making the leaves tremble, and greeted the children in his usual way, in rhyme.

"Good evening, dear children, the moon's shining bright!
Come hop on my train for a lovely surprise tonight!
Where the cold winds are blowing, a friend waits for you,
it's a sweet little secret... come quickly, choo-choo!"

The children did not need to be told twice. They climbed laughing onto the soft carriages, and Toby set off slowly, then quickly, across the meadows covered with dew that sparkled like tiny diamonds under the moon.

The little train ran and ran, until the woods grew darker and colder. The air smelled of mint. Toby stopped in front of an icy stream, and on the other side of the stream there was a hill, and inside the hill a big glittering cave opened up.

"How wonderful," said Skye softly.

It was the Cave of Sparkles. Its walls were made of ice crystal, and they took the light of the moon and bounced it into a thousand little silver dots, as if inside there was a rain of stars. From the ceiling hung the stalactites, those long thin points of ice, and when a drop brushed them they rang tin, tin, tin, like little bells.

But the children soon saw something else. Near the stream, all shivering, there was a snowman. Not one of those still snowmen you build in winter: this one moved, and instead of walking he glided, leaving behind a trail of sparkling frost.

"Hello," said Lily, coming closer. "Who are you?"

The snowman turned, took off his little carrot nose and put it back on, because he was nervous.

"My name is Snowy," he said in a little voice that trembled. "And you, little girl, are very brave to come all the way here at night."

The children looked at each other. Dash frowned.

"What does brave mean?" he asked.

Snowy held tight his little blue checkered scarf, which he always kept with him, and explained.

"Brave means not being afraid. It means going on even when it's hard, even when the others stop."

Lily smiled. She liked that new word. And it suited her very well.

"Then yes, I am brave," she said. "But why are you shivering so much, Snowy?"

The snowman pointed at the stream with his little snow hand, and his voice broke.

"I came out to look at the moon. It's the most beautiful night of the year! But the wooden bridge that takes me back into the cave has broken. Look."

The children looked. In the middle of the icy stream, the old wooden bridge had collapsed: the planks were in the water, carried away by the current. You could no longer cross to the other side.

"Then let's build another bridge," said Ziggy.

"There's no time," moaned Snowy. He took off his little carrot nose again. "Look over there, at the horizon."

Everyone turned. Far away, behind the trees, the black sky was beginning to grow just a little lighter. It turned pale grey, then pale pink.

"Dawn is coming," whispered Snowy. "And with the dawn comes the warmth of the sun. I am made of snow. If the sun finds me out here, I... I melt."

There was a silence. Skye put her hands to her mouth. The children's hearts began to beat faster too, because they had understood: they had to bring Snowy back into the cold cave, on the other side of the stream, before the sun came up. And the bridge was gone.

Dash looked at the icy water.

"We can't cross on foot, it's too cold," he said.

Skye had teary eyes.

"So what do we do now?"

That was when Lily stood up straight, hands on her hips, and her blue eyes shone brighter than the moon.

"We'll build a new path ourselves," she said. "With what we have here. Leaves and little stones. We won't give up on Snowy."

"Leaves and little stones?" repeated Dash.

"Yes! We'll put lots of wide leaves on the water, one next to the other, and make ourselves a walkway."

There was no time to think too much. The children ran under the trees and gathered armfuls of big leaves, the ones as wide as plates. They carried them to the stream and began to lay them on the water, one after another, to make a carpet.

"Quick, quick!" said Snowy, watching the sky grow lighter and lighter.

Lily laid the last leaf and put one foot on it, bravely, to test the walkway.

But the leaves were wet. And slippery. As soon as Lily put her foot down, the leaves slid away on the water, scattered, and the current carried them far off. The walkway melted away in a flash, and Lily almost fell into the stream: Ziggy grabbed her by the jacket just in time and pulled her back.

The leaf path would not hold.

The children were speechless. The leaves floated away, far off, and the sky was pinker and pinker. Snowy sat down on the ground and hid his face in his scarf.

"It's no use," he whimpered. "The leaves slip. We'll never make it."

Skye came close to Snowy and put a hand on his cold shoulder. Dash looked at the ground. Ziggy sighed too.

But not Lily. Lily looked at the water, looked at the leaves floating away, and she was thinking. Because being brave doesn't only mean not being afraid: it also means not giving up.

And all at once she understood.

"I know what went wrong!" she cried. "The leaves slip on their own because they are light and wet. We need something heavy underneath. First we put the flat stones, the big ones, as a solid base. Then the leaves on top, so our feet won't slip!"

The children lifted their heads. Now they had a plan. But the sky was lighter and lighter, and there was only one way to make it: to do it all together, each one with their own job.

"Dash, you're the fastest," said Lily. "Run and find the biggest flat stones, the ones that don't wobble."

"I'm on it!" said Dash, and he shot off like an arrow.

"Ziggy, you have a good eye. You choose which stones are right and how to place them, one next to the other in the water."

"Okay!" said Ziggy, and he began to arrange the stones carefully, testing that they were steady.

"Skye, you are sweet and gentle. You stay with Snowy, hold his hand and don't let him get scared."

Skye took Snowy's little snow hand in hers.

"I'm here with you," she told him softly. "Everything will be all right."

"And I," said Lily, "will carry the leaves and put them on top of the stones."

And so they began. Dash ran back and forth carrying flat stones, panting but never stopping. Ziggy laid them in the water carefully, one beside the other, like lots of hidden little steps, and pressed them to be sure they held. Lily came behind and covered each stone with a wide leaf, so their feet had a soft, non-slippery place to step. Skye, meanwhile, held Snowy's hand and sang him a little nursery rhyme to make his fear go away.

Stone, leaf, stone, leaf. The path grew over the stream, one step after another, and this time it held.

But the sun was coming. The first warm ray peeked out behind the hill, golden, and touched the tip of Snowy's hat.

"Quick!" cried Lily. "The path is ready! Let's get Snowy across!"

Snowy was shivering too much to glide by himself. And so they did the last thing, the most important one: they passed him from hand to hand. Skye helped him up onto the first stone. Ziggy held him while he put a foot on the first leaf. Lily took him by the little hand and guided him step by step, through the middle of the stream, over the stones covered with leaves. Dash waited for them on the other side with open arms.

One step. Two steps. Three steps. The sun was rising, the light grew warm on Snowy's back, and the children felt their hearts beating so hard.

With the last step, Snowy jumped down on the other side, right into the cool shade of the Cave of Sparkles. Safe. Just in time.

The sun came up all the way, but Snowy was now in the cool, inside his home, and he did not melt even a tiny bit.

For a moment no one spoke. Then Snowy began to laugh, and he took off and put back his little carrot nose three times in a row out of happiness.

"You did it! No... we did it. Together!"

As if to say thank you, Snowy glided into the cave and with his little snow hands touched the ice stalactites, one after another. Tin, tin, tin, tin! They rang like little bells, a sweet music that echoed through the whole cavern. And the cave, which always repeated the last words, answered: "together, together, together..."

And then the most beautiful thing happened. Above their heads, in the morning sky, colored lights lit up, dancing like ribbons of silk: green, purple, green, purple. It was the aurora, which lit up only for those who had a brave heart.

The children stood with their mouths open, huddled close together, watching those dancing colors.

"CHOO CHOO!"

Toby the Magic Train had come back to get them. They said goodbye to Snowy, who from the cave waved his little blue checkered scarf, and they climbed onto the carriages with their eyes still full of aurora. As the little train set off back home, Toby said his rhyme:

"On their own, the leaves just slip and float away,
but together, dear friends, we make magic today!
A stone, a leaf, and a friend by your side:
together we'll always get to the end of the ride!"

And as the sky turned pink and full of light, the four friends went back home, tired and happy, knowing something new and important: that on your own you sometimes can't do it, but together, each one helping with their own little piece, you can even save a snow friend from the first sun of the morning.