I am not Rick Riordan but please enjoy.
Percy's P.O.V.
I leaped out of my bed as cold sweat rolled down my flesh. Being a demigod I'm used to having nightmares but this one had been different. Usually when I have nightmares I'm scared of the monsters and prophecies, but this time I had no idea what had scared me. All that I remembered was a figure covered in shadows holding a small silver circle. His presence wasn't even really scary because after the things I've been through I don't get as scared by things lurking in the dark like I did when I was younger. His existence just seemed wrong, like he shouldn't really exist. Suddenly I heard a loud banging noise on my door.
"Wake up Seaweed Brain!" Annabeth shouted with her enchanting voice that could get me to do anything. "You can come in!" I yelled in response with a grin. The door creaked open and light burst into the room like a bomb had went off. When I could actually see again I admired Annabeth's blond curls and startling gray eyes. "What are you staring at fish boy?" she teased. "Just the love of my life," I returned with another grin. Annabeth giggled and sat down on my bed next to me. "What's this?" she asked as she picked up a crumpled piece of paper off the floor. Suddenly her gray eyes shifted from their previously happy look to one of concern. "Percy you might want to read this," she said before handing me the paper. As I read it my hand began to shake and sweat began to form on my forehead once more.
The note read, "Dearest Percy Jackson I am pleased to be inviting you to the sea of monsters for a family reunion. Please don't ignore this opportunity to finally meet the heir of the trident. Signed your brother,"