The four friends were playing hide and seek in Lori's garden. It was a morning with a light mist that made everything blurry, as if someone had blown talcum powder into the air.

"I'll find you all!" shouted Lori, who was the one counting. He covered his eyes with his hands and began: "One, two, three, four..."

Alex hid behind the big bush. Violet squeezed under the bench. Ellen, with her usual calm, was still deciding where to hide when Lori already reached twenty.

"...nineteen, twenty! Ready or not, here I come!" Lori turned around and started running. He was super fast, the fastest of all, and he loved to run. He found Alex in three seconds because a foot was sticking out from the bush. He found Violet in five because her blue eyes were shining under the bench. And Ellen was still standing in the middle of the garden with her hands behind her back.

"Ellen, you didn't hide!" laughed Lori.

"I was thinking about the perfect spot," she replied, calm as ever. "But you were too quick."

Fred, Lori's dad, appeared at the window. "Lori, don't run on the wet grass! You'll slip-" But he didn't have time to finish his sentence before Lori had already slipped on the damp grass and sat down on the ground with a thud.

"I'm fine!" said Lori, bouncing back up like a spring. His trousers were all green from the grass.

Christine, Lori's mum, shook her head. "That boy never stops."

At that moment, through the garden mist, a familiar sound was heard.

"CHUFF CHUFF!"

"Toby!" they all shouted.

The magic train appeared from the fog like a cheerful ghost. He puffed out steam that sparkled with all colours, as if he had eaten a rainbow. His round eyes were brighter than usual and his wheels turned slowly, with a rhythmic clicking.

Toby the Magic Train stopped in front of the children and spoke with his singing voice:

"Good morning friends, what a lovely day!
Today I'll take you to a room not far away,
where toys are waiting for children to play,
but help is needed, come without delay!"

"A playroom?" Lori jumped up. "What are we waiting for? Let's get on!"

Christine straightened his jacket collar. "Be careful," she said.

"Mum, I'm always careful!" replied Lori, who was never careful, but said it anyway.

They all climbed onto the train. Lori stood up, gripping the edge, with the wind ruffling his hair. The train crossed a field of giant soap bubbles, then a forest where the trees had leaves made of coloured paper, and finally slipped through an enormous door that appeared from nowhere.

When they got off, they found themselves in a huge room. It was the biggest playroom they had ever seen. There were rocking horses as tall as real horses, wooden soldiers as big as children, towers of coloured blocks reaching up to the ceiling, and in the centre of the room a soft carpet with a map of the world drawn on it.

"This is the Prince's Playroom!" said a squeaky voice.

The children looked around. From behind a castle of building bricks popped out a marmot. She was small, furry, with two round eyes like buttons and a little snout that never stayed still. She whistled constantly: short whistles, long whistles, whistles that went up and down.

"Hello! I'm Whistle!" said the marmot, whistling between words. "I'm the guardian marmot of this room. I whistle to warn everyone when something happens!"

"What's a marmot?" asked Alex.

"A marmot is an animal that lives in the mountains," explained Ellen, who always knew these things. "They're famous because they whistle very loudly to warn other marmots of danger."

"Exactly!" Whistle made a whistle so high-pitched that everyone covered their ears. "Sorry! Sometimes I overdo it. But today I have a serious problem." Her little snout wrinkled and she looked almost sad.

"What problem?" asked Violet, crossing her arms.

Whistle pointed to the centre of the room. "Do you see those two groups of toy soldiers?"

The children looked. On one side of the room there were red soldiers, on the other side blue soldiers. They were all standing still, motionless like statues, but they had very angry faces painted on their wooden heads.

"The red soldiers want to play on the carpet with the map. And the blue soldiers also want to play on the same carpet. But there's only one carpet! And since this morning they refuse to move until they decide who gets to use it." Whistle whistled sadly. "And without them marching and playing, the whole room has stopped. The rocking horses don't rock anymore, the blocks don't stack and even the balls don't bounce."

Lori looked at the situation and said immediately: "Easy! We have a race! Whoever gets to the carpet first, uses it!"

He got into starting position, ready to run and demonstrate.

"No, wait!" said Whistle. "Already tried. The reds are as fast as the blues, they always arrive together and argue even more."

"Then we divide the carpet in half," suggested Violet, practical as always.

"Tried that too. But the map on the carpet has the sea on one side and the mountain on the other, and both groups want the mountain."

Lori sat down on the floor, a bit annoyed. "So what do we do?"

Ellen approached the soldiers and looked at them one by one, with her usual calm. "Maybe the problem isn't who uses the carpet. Maybe the problem is that they've never tried playing on it together."

"Together?" Whistle tilted her head. "They've never thought of that."

"Let's try," said Ellen.

But Lori was impatient. "I have a better idea! I'll invent a new game so fast that they won't have time to argue!" He jumped up and started moving the soldiers onto the carpet, mixing reds and blues randomly, moving them quickly like pieces on a chessboard.

A red soldier fell. Then a blue one. Then three together. Lori was going too fast and the soldiers were falling like skittles.

"Lori, slow down!" said Violet.

"No no, wait, almost done!" Lori moved another five, but they all fell. The nearby building brick castle shook and collapsed too, in an avalanche of coloured pieces.

Lori stopped, his hands full of fallen soldiers. He looked at the disaster. "Oh," he said, quietly.

Whistle made a long, sad whistle.

Alex and Violet looked at Lori. Ellen came closer and put a hand on his shoulder.

"It doesn't matter," said Ellen. "You went too fast, but we can try again."

"But I broke everything," said Lori, and for the first time he was truly still.

"You didn't break anything. The soldiers just fell down. They can be stood up again," said Ellen. "But this time, let's do it slowly."

Lori took a breath. He wasn't used to doing things slowly, but he looked at Ellen and nodded.

They began together. Ellen took a red soldier and a blue one and placed them next to each other on the mountain of the carpet. "One red and one blue. They're a pair."

Lori picked up another soldier, but his hand was trembling. He set it down too quickly and the soldier wobbled.

"Slowly," said Ellen.

Lori gritted his teeth. He tried again. This time he set it down slowly. The soldier stayed standing.

"Well done!" said Alex.

Lori smiled. He picked up another one. Slowly. Standing. Another one. Slowly. Standing. Violet helped arrange them in a row. Alex built a small bridge of bricks between the mountain and the sea.

It took time. Lori had to try again several times because his hand went too fast out of habit. But every time he made a mistake, he didn't get angry. He breathed and tried again.

When the last soldier was in position, something magical happened. The soldiers began to move on their own! The reds and blues marched together across the map, crossing Alex's bridge, climbing Ellen's mountain, and sailing the sea with little boats that Violet had made from pieces of paper.

The room came alive. The rocking horses started rocking again. The blocks stacked into very tall towers. The balls bounced happily.

Whistle began to whistle with joy, a whistle so loud and happy that it echoed throughout the room. "They've learned to play together! And you've understood that things must be done with patience!"

Lori watched the soldiers marching happily. "You know what, Whistle? The first time I made a mistake because I was going too fast. But I tried again, and the second time it went better."

"We learn by making mistakes!" said Whistle, whistling the phrase as if it were a little song. "And by trying again, we succeed!"

Whistle hopped over to a hidden drawer behind the rebuilt castle and pulled out four special soldiers, one for each child. They were small, colourful, and had enormous smiles painted on them.

"These are the Soldiers of Perseverance," said Whistle. "When something doesn't work out, look at them and remember: try again."

Lori clutched his soldier. It was blue and red together, half and half. Like the two teams that had learned to play together.

They returned to the big room where Toby was waiting for them, shiny and puffing.

"What good children you have been,
the soldiers you have helped, I've seen!
Slowly, slowly, without haste,
the room is now perfect, nothing's gone to waste!"

The children climbed on laughing. Lori, for the first time, didn't run towards the train. He walked. And when he got on, he sat down calmly, clutching the soldier in his hand.

As the train took them home through the paper forest and the field of bubbles, Lori looked out of the window. The mist had lifted and in its place was blue sky.

When they arrived, Fred was in the garden waiting for them.

"So, how did it go?"

Lori ran to meet him — because running was stronger than him — but he stopped right in front of his dad, without crashing into him like he usually did.

"Dad, do you know that we learn by making mistakes?"

Fred smiled. "I know. And what did you learn?"

"That when something doesn't work out, you shouldn't get angry. You should try again, but more slowly."

"And who taught you that?"

"A marmot who whistles and some stubborn soldiers," said Lori, showing his blue and red soldier.

Fred picked him up, which he didn't often do because Lori always wriggled. But this time Lori stayed still, resting his head on his dad's shoulder, with the soldier clutched in his fist.

And this is the most important thing that Lori and his friends learned that day: that making mistakes isn't a problem, because we learn by making mistakes. And that when something doesn't work out the first time, you just need to have the courage to try again, maybe a bit more slowly, and in the end you'll succeed.