Falling asleep that night was easy. The bubble of water into the fountain and clean ocean smell was incredibly soothing, and the bunk with its sea colored silk sheets unbelievably comfortable but is it any wonder I had nightmares after the day I'd had?

They started peacefully enough – the worst nightmares always do – I was standing surrounded by trees under a high bare hill. A boy was lying with his head pillowed on a big oak root, half covered by old brown leaves. He had thick black hair with a wave in it, like mine, and a very straight nose like a Greek statue. He was wearing the Camp Half-blood uniform of orange t-shirt and shorts and I knew he could only be my missing older brother Percy Jackson. I bent to shake him awake but my hand went right through his shoulder like I was ghost – or he was. Then the long yellow grass on the hill above us rippled and formed into a face with horrible black hollows for eyes and a mouth stretching wider and wider in a howl of rage and frustration.

I crouched down next to Percy clutching the pearl around my neck. The face on the hillside went on screeching. The trees heaved and shook but the ground under Percy and me was perfectly still, not even a leaf stirring. Slowly I straightened up. 'She can't get us,' I said to my unconscious brother. 'Something – somebody's protecting us… I mean you,' because I wasn't really there at all.

Next thing I knew I was skimming over a choppy sea just inches above the waves. And there was the storm giant churning the ocean to foam with lightning flashing around him as he attacked airplanes and big container ships. Sirens were going off and I could almost hear the SOSes crackling through the ether.

The next instant the storm was gone and I was in some kind of underwater cave eerily lit by glowing seaweed and darting fish streaked with luminous spots like tiny Christmas lights. Powerful currents swirled around and through me churned by the thrashing of pair of huge sea serpents, their shiny black sides glistening like eels' skin. Three small, bright shapes darted in and out between them, dodging contracting coils and gnashing teeth.

Before I could figure out exactly what was going on I was whirled away into another place. I was still underwater but standing on a pearl cobbled street between buildings of coral and shell. I pressed myself against a wall as mer-people streamed past. They were blue skinned and pointy toothed like my guards but all sizes including little mer-kids and babies in their parents' arms. And they all looked terrified. The sea floor shook, walls swayed and cracks opened in the road. The mer-people gave high, dolphin-like screams and swam faster. I wanted to go see what they were escaping from and the next instant I was at the other end of the street floating above a sort of terrace behind a big man with two legs instead of a fishes' tail. He was wearing pearly scaled armor and had black hair floating around his head and a glowing golden trident in his hand. I looked over his shoulder down into a sort of square. The stone pavement was cracked and buckled with glowing red lave flowing out of a fiery crater in the center, then a massive flaming arm punched upward and I screamed.

The man in the pearl armor turned around and it was Philip – Poseidon – my dad. "Daddy!" I tried to swim to him but couldn't without a body. He shot a quick glance over his shoulder where a huge head was emerging from the crater after the arm then reached for me and all of a sudden I was solid, hanging on to his big, warm hand with all my might. "Daddy, I found Percy he's safe -"

"I know," he interrupted. "Hera is protecting him – blast her interference! Pearl, I want you to stay in camp even in your dreams!

"But –"

"Please, sweetheart. Bad enough Percy's in danger. Keep yourself safe and take care of your little brothers and sisters for me." Behind him the lava giant roared as it pulled itself out of the crater. The ground heaved.

"Daddy!"

"Go Pearl!"

My eyes popped open. I lay in my bunk heart pounding. The abalone walls reflected enough of the moonlight outside for me to see Morgan twitching in his bed opposite mine. Suddenly he hurtled upright.

"Look out, Dad!"

"Morgan!" He blinked at me, eyes reflecting glassily in the dim light. "Bad dream?"

He sucked in a breath. "Yeah, Dad was fighting a lava giant –"

"But that was my dream!" I blurted. We looked at each other.

"You don't think -" he was beginning when somebody banged on the door. We almost didn't answer then it occurred to me that monsters wouldn't knock so I did.

It was Grover, Percy's goaty friend. "Chiron wants you up at the Big House," he panted like he'd run all the way. His yellow eyes were round but the pupils were all slitty like a cat's.

Chiron had pillow hair and was wearing a pajama top on his human half and curlers in the tail of his horse half. A big guy covered with eyes – I mean literally covered with blinking blue eyes – was with him, and Annabeth who didn't look like she'd been sleeping and Jason and Clarisse who looked as if they had.

Three kids were sitting on one of the sofas, kind of shell-shocked, holding mugs of cocoa. One was a really beautiful, exotic looking girl with olive skin and dark hair about my age with a much younger blond girl on one side and an even littler boy with light brown hair on the other. All three had sea green eyes and by now I knew what that meant. These just had to be the little brother and sisters Dad wanted me to look after for him – and that meant that my nightmare wasn't just a dream.

I stuck out my hand. "Hi, I'm Pearl. This is Morgan. We're your sister and brother."

The oldest girl didn't turn a hair, just took my hand and gave it a shake. Next to her the little blond wriggled in delight. "Another sister, I've always wanted one now I've got two!"

Morgan shook hands with the little boy. "We got to stick together," he said, "we're outnumbered."

"I'm Leakalani Cooke," the dark, pretty girl began.

"She's a princess!" our blond sister put in happily.

"My mother's a Hawaiian High Chiefess," Leakalani explained, "that's kind of like a princess. Anyway this is Shelly and Jimmy Goldman."

"Our mom is an Oceanographer," little Jimmy told Morgan. "That's how she came to meet Dad."

"We didn't know he was a god," Shelly continued, "but we always knew he was magic. He was the one who made it so Mom could breathe underwater and we can too, and turn into mermaids –"

"Seal boy!" her brother barked.

She ignored him. "And talk to fish and dolphins and seals and things. So our dad being Poseidon made perfect sense."

Well somebody sure wasn't having any problems adjusting!

I guess centaurs – like a lot of grown-ups - take a little time to wake up all the way. Chiron finally put down his coffee cup and joined in the conversation. "Surely Poseidon assigned someone to watch over you, where are your protectors?"

All three kids looked unhappy. "We don't know," Leakalani said. "We had to leave them behind in the caves. We don't know what happened to them."

"They're gods, they've got to be okay," little Shelly said hopefully.

"Gods can't be killed any more than monsters, right?" Jimmy asked Morgan.

"That's right," Jason answered reassuringly. "If they were underwater they'd be able to draw power from the sea itself. I only managed to defeat Proteus by getting him up on land, and I certainly didn't kill him."

I wondered why he'd be fighting a sea god in the first place but this wasn't the time to ask.

"Start at the beginning, children," Chiron said. "Leakalani first, please."

She took a gulp of her cocoa. "Okay, like I said my mom's Hawaiian. We live on her ranch on the Big Island -"

"Ranch?" several people said together, including me.

Leakalani pulled a face. "Yeah, ranch. Hawaii isn't all beaches and palm trees like on television. Mom owns hundreds of acres inherited from the old chiefs and we raise cattle and horses. In fact she met Dad at a horse show."

"So did my mom," I said. "Dad likes horses."

"Poseidon created horses," said Annabeth.

That surprised me, "Really?"

"Yeah, that's why I can talk to them." Leakalani went on: "Anyway a month or so ago we started having lots of earthquakes and I started feeling sick to my stomach all the time. We didn't realize there was a connection until Pele, she's the Hawaiian goddess of volcanoes and a sort of relative on my mom's side, came down to warn us – she's friendly with Dad and knew all about me.

"Pele said she wasn't making the earthquakes, she didn't know who was and she didn't like it one bit. Neither did Mom. They figured it had to have something to do with me – that's when they told me who Dad was – and Mom called the Aggers, the old haoles who rent our beach house –"

"The old what?" Clarisse interrupted.

"Haole that's what we call white people. We don't mean it in a nasty way. Anyway the Aggers are the sea-gods Dad assigned to guard me. They said I'd better come here right away – I was supposed to go this summer –"

"Me too," Morgan, the Goldmans and I all said together.

"They were talking about if it would be safe to take a ship or if we should swim when my stomach started hurting again and then the ground started shaking and it went on and on – real earthquakes never last very long you know -" Shelly and Jimmy nodded as if they did know that. "The grown-ups all ran outside," Leakalani continued. "I couldn't run, it hurt so much, but I dragged myself to a window and I saw that the ground between our house and the barn was heaving upward and cracking. Lava came out and all of a sudden I just knew that something was trying to make a volcano right in the middle of our backyard, something that wasn't Madam Pele and had no right. It's our island, Pele's and Mom's and mine, and something that didn't belong was invading it!" her forehead wrinkled in a frown. "I got angry. My stomach didn't hurt so much – or maybe it was different kind of hurt…. I don't really understand what happened next. I could feel the whatever-it-was pushing, trying to get out to attack us. And I – somehow – pushed back. It was like we were on either side of a door. It wanted to open the door to get in and I wanted the door closed to keep it out. We shoved harder and harder. It hurt so much but I didn't care anymore. Nothing mattered but making the thing go away! The ground shook and shook, the windows were rattling like anything and stuff was falling off shelves and the table…I was winning, I knew I was winning. I pushed and pushed and I shoved what-ever-it was back down into the earth deeper and deeper…"

She broke off with a shrug. "That's all I remember. I blacked out or fainted or something and when I woke up I was at the Goldman's place in San Diego."