Once upon a time, in a warm, green valley filled with singing birds and the gentle bubbling of streams, there lived a herd of gentle dinosaurs called hadrosaurs. They were large and friendly, with long tails and duck-billed mouths perfect for munching on leaves. The valley where they lived was their safe home, with tall trees for shade, soft grass for sleeping, and most importantly, a sparkling clear waterhole in the center, where all animals came to drink.

Among the herd was a young dinosaur named Toki. Toki was curious, with bright eyes and a heart full of wonder. He loved to run alongside butterflies, splash in the waterhole, and ask questions about everything he saw. But sometimes, Toki would forget to finish small tasks or wander off before he was done with his chores. He was still learning what it meant to be responsible.

One golden morning, as the herd grazed quietly, the ground began to tremble with distant footsteps. The old leader, Grandad Sorus, lifted his head and sniffed the air. “It’s time to migrate, friends,” he announced, his deep voice rolling across the valley. “The big rains are coming, and we must follow the river to safer grounds until the storms pass.”

The herd buzzed with excitement. Migration was a big adventure! But Grandad Sorus wore a look of concern. “The waterhole is the heart of our valley. If it dries up or gets dirty, the valley animals will have no place to drink. This year, someone must stay to guard it.”

The herd grew quiet. Guarding the waterhole meant staying behind, all alone, while everyone else went on their journey. Toki’s heart leapt at the thought of such an important job, but it also fluttered nervously. Grandad Sorus looked around and said, “We need someone who is brave and kind. Someone who can remember to check the water and keep it safe for all who visit.”

Before Toki could speak, his mother nudged him gently. “Why not Toki?” she said with a smile. “He loves the waterhole and all the animals that visit it.”

Grandad Sorus knelt down so his big eyes were level with Toki’s. “Would you like to try, Toki? It’s a big responsibility.”

Toki’s tail thumped the ground. “I’ll do my very best, Grandad Sorus! I’ll guard the waterhole with all my heart.”

So, on the morning of the migration, the herd gathered beside the waterhole. Grandad Sorus gave Toki a necklace made of river stones, the symbol of the guardian. “Remember, check the water every morning and evening. Keep the wild boars from digging up the banks. If you see the water getting low or muddy, find a way to fix it. And always be kind to the thirsty travelers who come to drink.”

Toki promised, even though his voice was a little wobbly. He watched as his family and friends set off down the winding river path, their shapes growing smaller and smaller, until the valley was quiet and still.

That first day, Toki felt very proud. He walked a careful circle around the waterhole, inspecting every pebble and blade of grass. He chased away a group of noisy crows who tried to toss sticks into the water. He helped a family of turtles find the softest mud near the edge. When the sun set, Toki sat beneath a willow tree, feeling grown-up and important.

But as night fell and the stars twinkled, Toki began to feel lonely. Strange shadows danced in the moonlight, and the hoots of owls echoed through the trees. Toki curled up and hugged his tail, missing the warm comfort of his herd.

The next morning, Toki splashed water on his face to wake himself up. He remembered Grandad Sorus’s words and walked around the waterhole to check that everything was safe. Suddenly, he heard a rustling nearby. Out from the bushes came a family of tiny, squeaky mammals with shiny eyes.

“Excuse us, Guardian Toki,” the mother said, “the grass is too tall for us to reach the water. Could you help?”

Toki smiled. He tromped gently around the edge, flattening the grass so the little ones could scamper down and drink. They chirped their thanks, and Toki felt his heart fill with pride.

Just as Toki was about to take a sip himself, he heard grunting and snorting. It was the wild boars! They loved to dig up the banks, making muddy holes that could spoil the water.

Toki took a deep breath and stood tall. “Please, friends,” he called, “the waterhole is for everyone. We have to keep it clean.”

The boars grumbled, but Toki offered to roll a big log to the other side of the waterhole. “You can dig near the log for your mud baths, but please leave the banks alone.”

The boars agreed, and soon they were happily rolling in their new mud spot, away from the water’s edge.

Days passed, and every morning, Toki checked the water, greeted the visitors, and solved little problems. Once, he helped a thirsty deer who had twisted its hoof. Another time, he showed a flock of birds where to find berries. Toki felt proud of his work, but he missed his family.

One afternoon, dark clouds gathered above the valley. The wind howled, and rain poured down, turning the ground into slippery, sticky muck. The waterhole began to swell with rushing water from the hills. Toki remembered Grandad Sorus’s warning: “If the water gets too high, it will spill over and wash away the banks.”

Toki hurried around the edge, using his strong tail to pile up stones where the water was rising. He called to the turtles and the little mammals, “We must all help!” Together, they pushed pebbles and mud to build a wall. The rain kept falling, but Toki didn’t give up. He worked until his legs ached and his skin was slick with mud.

Finally, the rain stopped, and the waterhole was safe. The animals cheered, and Toki felt more responsible than ever before.

As days turned into weeks, Toki grew stronger and wiser. He learned to listen for trouble, to share the water with all, and to use his clever mind to solve problems. He even made friends with a wise old frog who told stories each night, keeping loneliness at bay.

One morning, as the sun rose golden over the valley, Toki heard a familiar rumbling. He raced to the top of the hill and saw his herd returning at last! Grandad Sorus led the way, his eyes bright when he saw Toki.

The herd ran to the waterhole, finding it clean, full, and safe. “Toki!” cried his mother, nuzzling him. “We are so proud of you!”

Grandad Sorus placed a second necklace of river stones around Toki’s neck. “You showed what it means to be responsible, Toki. You cared for the waterhole and all who needed it. You did not give up, even when you were scared or lonely.”

Toki felt taller than the tallest tree. That night, as the herd gathered by the waterhole, Toki told them stories of his adventure—helping the little mammals, building the wall in the rain, and learning from the wise old frog.

As the stars twinkled above, Toki knew that growing up meant helping others, keeping promises, and doing your best, even when it was hard. He snuggled close to his family, with the gentle sounds of the waterhole nearby, and drifted off to sleep—proud, happy, and very, very loved.

And so, in the green valley under the watchful moon, Toki the young dinosaur dreamed of more adventures, ready for whatever new responsibilities tomorrow would bring.

The end.