Ok, so this is my first Percy Jackson fanfiction so I would appreciate any and all reviews. This Fanfiction is set from the end of the last Olympian or the last book of the Percy Jackson and Olympians series leads on to the heroes of Olympus books with some alterations to fit with the story. Some people may not like the changes to the story but please no hateful reviews but a would like some constructive criticism so I no what i need to improve on. Ok so now that's sorted on to the story...

Disclaimer:- I don't own any of the characters from Riordan's books that are in this story apart from the few OC that i have made up myself.

Percy's POV

As he walked back to the doors to the elevator where his girlfriend Annabeth was waiting for him Percy thought about what his father had just said to him...

*FLASHBACK*

"Thank you Percy, for now i can finally claim my other two children." Poseidon said gratefully

"WAIT" Percy said in disbelief "I have to other siblings?"

"Yes, twin sisters, Cleo and Katrine." Answered Poseidon.

"And why didn't you tell me before." Demanded Percy Angrily.

"I wanted to make sure you were ready, and anyway I wouldn't have been able to claim them before now without Zeus punishing them." The god explained calmly.

Percy nodded in understanding though it still angered him know his father had kept something this big from him for so long. "How old are they?" He asked thinking back to when he first found out he was a demigod at twelve years old.

"Just turned fifteen" Poseidon replied, " They live close to your camp, You will meet them sometime next week near long island so be ready."

*FLASH FORWARD*

Percy shook his head, over whelmed with new piece of information. He had two younger sisters!

Cleo's POV

Cleo sprinted down the beach, her feet sinking in the soft golden sand of long island beach, as she raced her twin sister, Katrine to the water's edge. With a burst of energy she sped to the finish line only to find Katrine was already there. She stopped on the sand near the edge opposite where her sister was stood in turquoise shorts and a white t-shirt ankle deep in the water.

Using her fingers to pull the worst of the knots out of her wavy black hair Katrine struck a pose and bellowed. "I Katrine, have proved that my speed is far superior to all those to dare to oppose me, including my younger twin Cleo!"

"only by an hour!" Cleo protested before shoving her sister so that she toppled over and ended up sat in the cool green sea water.

Katrine pulled a face that sent Cleo rolling on the sand in a fit of giggles only to have her sister grab her arm and drag her so she was soaked from head to toe. Cleo pulled herself up so she was sat next to her twin. They sat there i silence the only sounds to be heard were the rustling of the surrounding trees, the screeching of the sea gulls the distant sounds of the traffic in new York and the sound of Cleo's dark brunette hair dripping into the shallows for five long seconds. One...two...three...four...five.

Both girls looked at each other before both sisters burst out laughing and splashed each other under the sun.

Unknown POV

Unbeknown to the children they were being watched by a figure stood in the shelter of the trees.

"Yes little demi-gods enjoy the heat while it last because once I get my hands on you there won't be a single soul able to hear you scream!"

Well there you go. I'm sorry if this was a little long and boring but there's nothing i can do about it. Review and follow if you want another chapter and ill upload the next one if i get enough.