Nanna Banna lives by a shining castle under the sea. She is a kind mermaid with a shimmering tail. She loves to sing soft songs. She loves to play near the castle towers. She has a small doll friend named Doll. Doll is soft and has bright blue hair. Doll likes to watch bubbles float up. One day Doll lost her special seashell. The seashell was small and pink. It held the sound of the waves. Doll felt sad without the seashell. Nanna Banna promised to help. She swam to the coral gardens. She looked under green plants. She looked under white rocks. But she did not find the shell. She asked a tiny fish for help. The fish pointed towards the castle gates. Nanna Banna dove down. She glided past tall seaweed. She reached the castle gates. The gates were made of shiny gold. She pushed them open with her tail. Inside she saw a long corridor. The corridor was full of colorful shells. She swam slowly and softly. She did not want to make a loud sound. She heard a deep rumble. She looked closer in the shadows. A big Yeti stood by the wall. The Yeti had white fur and big feet. The Yeti looked grumpy and tired. Nanna Banna felt a little scared. But she remembered her promise. She took a deep breath. She waved at the Yeti. The Yeti blinked his big eyes. He asked why she was there. Nanna Banna said she wanted a lost seashell. She spoke in a gentle voice. The Yeti fumbled his words. He said he had not seen the shell. He looked around the corridor. He scratched his big head with a hairy paw. Nanna Banna asked if he could help. The Yeti sighed softly. He said he once heard a clink near the spiral stairs. Nanna Banna thanked him. She swam to the spiral stairs. The stairs curled up like a snail shell. She peeked into a small room. The room was warm and calm. She saw many shining seashells. She moved closer to the shells. She looked behind a purple shell. Her heart beat fast. She did not see her pink shell. She heard a soft giggle. She turned around quickly. Doll floated near a small golden chest. Doll held the pink shell in her hands. Doll giggled again softly. Nanna Banna smiled with relief. She hugged her doll friend. She said she was happy to have found it. Doll said she had found it all along. She hid it for a secret game. Nanna Banna laughed with joy. Then they heard the Yeti rumble. They turned and saw him at the door. He looked shy now. He said he was happy they were safe. He had carried them in his heart. Nanna Banna thanked him kindly. She said he was brave and wise. The Yeti smiled for the first time. He gave Nanna Banna a glowing pearl. It shone with soft light. He said it was a gift of thanks. Nanna Banna placed the pearl on her tail. It glimmered in rainbow hues. Doll clapped her tiny hands. Nanna Banna hugged the Yeti. She said friends come in all sizes. The Yeti nodded and waved goodbye. Nanna Banna and Doll left the castle. They swam through the seaweed gardens. They saw schools of bright fish. They heard the waves sing. They reached their home by the coral. They placed the pearl on a high shell shelf. They placed the seashell on their window. They sang a soft melody together. Their song filled the blue waters. The fish danced to the tune. The Yeti watched from the castle window. He waved and hummed along. Nanna Banna felt proud and calm. She learned that kind words help friends. She learned that a promise is a treasure. She went to sleep under a shell canopy. Doll rested on her shoulder. The pearl glowed softly in the dark. The sea whispered a lullaby. They dreamed of new adventures. They smiled in their sleep. Tomorrow they would explore again. The castle would welcome them back. The sea would share more secrets. They knew they were never alone. The world under the waves was full of wonder. And they lived happily in their bright ocean home.