Once upon a time, high above the fluffy white clouds, lived a family of tiny, shimmering Sprites. These weren't ordinary sprites; they were Rainbow Sprites, each one sparkling with the colours of the rainbow itself! Papa Sprite was a deep, rich red, Mama Sprite a sunny yellow, and their little one, Pip, was a vibrant, bouncy blue.

Pip loved to play hide-and-seek with his parents amongst the clouds. But one day, a big, grumpy storm cloud rolled in, all grey and scowling. It grumbled and grumbled, spitting out huge drops of rain. The rain poured down to the earth below, washing everything clean and fresh.

Pip, snuggled close to Mama Sprite, watched the rain fall. He'd never seen so much water! "Mama," he whispered, his tiny voice barely audible over the rumble of thunder, "What's happening? Why is it so wet?"

Mama Sprite smiled, her yellow glow a little dimmer in the grey light. "My little one," she explained, "the grumpy storm cloud is just having a big cry. He’s been holding all those raindrops inside him for a long time, and now he's letting them all go."

Pip tilted his head. "But… what are those raindrops doing?"

Mama Sprite pointed towards the earth. "Look, Pip! Each little raindrop is like a tiny, tiny prism. A prism is a special kind of glass that can split light into all its colours."

Pip, still a little confused, asked, "What's light?"

"Light, my dear," Papa Sprite chuckled, his red glow peeking through the clouds, "is all around us! We can't see it directly, but we can see the things it bounces off of, like the flowers, the trees, and even you!"

Mama Sprite continued, "Sunlight, Pip, is actually made up of all the colours of the rainbow, all mixed together. We just see it as white light. But when the sunlight shines through a raindrop, something magical happens!"

She explained, using her shimmering light to draw a picture in the clouds. "Imagine the sunlight entering a raindrop. It's like a tiny beam of white light entering a tiny, sparkling prism. Inside the raindrop, the white light gets bent and separated into all its different colours – red, orange, yellow, green, blue, indigo, and violet."

"Wow!" Pip exclaimed, his blue glow brightening with excitement.

"That's right!" Papa Sprite added. "Each colour bends at a slightly different angle, so they separate and we see them as distinct colours. It's like a magical colour show put on by the raindrops!"

Mama Sprite pointed to the earth. "And after the rain stops, and the sun peeks through the clouds, we see all those separated colours reflected back to us. It’s like a million tiny raindrops are all showing off their own little rainbows. When all those little rainbows join together, we see one big, beautiful rainbow arching across the sky!"

Pip gasped, his eyes wide with wonder. "So the grumpy storm cloud helps make rainbows?"

"Indeed, my little one," Mama Sprite said, "The storm cloud provides the raindrops, the sun provides the light, and together, they create this beautiful and magical sight!"

Papa Sprite added, "And each rainbow is unique! You'll never see two rainbows exactly alike, just like snowflakes."

Pip, now understanding, felt a surge of joy. He realized that even something as gloomy as a storm cloud could lead to something as beautiful as a rainbow. He snuggled closer to his parents, his blue glow reflecting the colours of the imaginary rainbow they had painted in the clouds. From that day on, every time Pip saw a rainbow, he remembered the grumpy storm cloud, the magical raindrops, and the wonderful story his parents told him about the secret of the rainbow’s colours. He learned that even sadness and storms can lead to beauty and wonder, and that even the smallest things, like a raindrop, can hold the magic of the world. And every time it rained, Pip looked forward to the possibility of seeing a brand-new, shimmering rainbow – a reminder of the magical power of nature and the love of his parents. He knew that even though rainbows might disappear, the memory of their vibrant colours and the joy they bring would always stay with him.