There could be various interpretations of Percy's dream about his daughter Kelly in fanfiction. Maybe in the fanfic, this dream is a premonition of something important related to Kelly's future, like a special power she will develop or a great adventure she'll embark on.
Perhaps in the fanfiction, Percy dreams of Kelly in a perilous situation. This could then drive the plot as he tries to prevent this situation from becoming a reality in the real world of the story.
A less obvious but still present theme is the idea of legacy. Percy has a great legacy in the world of the stories, and his daughter has to deal with the expectations and responsibilities that come with being part of that legacy. This can add a lot of depth to the stories as she tries to make her own mark while living in her father's shadow.
Percy would use his combat skills. He has a lot of experience in fighting monsters, so if any threats come near his daughter, he'd be ready to fight them off with his sword. He'd also use his strategic thinking to outwit enemies.
They might become more protective. Since they are dreaming of having a daughter, they would start to think about all the potential dangers she could face. Their relationship could grow deeper as they bond over their shared hopes and fears for their future child.
One possible plot could be that in their dreams, they see their daughter growing up in a world where the threats they faced are no more. She is strong and confident, trained in the ways of the demigods. They dream of her making friends easily at Camp Half - Blood and having a special bond with the nature spirits there.
There's also a piece that focuses on Percy's dream daughter in a modern - day setting with a touch of mystery. In this fanfiction, the daughter discovers her true identity and has to deal with the challenges that come with being Percy's child. It's a great read if you like stories that blend the ordinary with the extraordinary.
Percy is likely to be heartbroken. He may initially be in a state of shock, not being able to believe that Annabeth has left him and their daughter. He might feel angry as well, feeling betrayed by her sudden departure.
Perhaps it's an old acquaintance from Percy's past who he reconnects with after leaving camp. They fall in love and she becomes the mother of his daughter.
Well, they could go on an adventure together. Maybe face some mythical creatures that are threatening their world. It would be really cool to see how Percy uses his skills and experience to protect his daughter and teach her about the world of gods and monsters.
A fanfiction that stands out is the one where Percy, daughter of Poseidon, goes on a quest to find a lost artifact that has the power to either save or destroy the underwater world. Along the way, she meets various mythical creatures and forms unexpected alliances. The author does a great job of painting a vivid picture of the underwater realm and Percy's growth throughout the story.