"John. I have to go back. I need to ask advice on what to do," Mary said.

"Yeah," John agreed, "but if there's not gonna be a quick cure for Dean, we're going to have to let him go and live on dry land. He can't remain for ever with us here in this pool."

"I'm aware," Mary answered. "If there's anyone who can help Dean prepare for that eventuality, it's you John," she pointed out.

Turning to her youngest she ruffled his hair. "Sammy, you're sure you don't want to come home with me. Staying here won't help Dean, and dipping down into the water to breathe every few minutes is gonna tire you out."
Vehemently, Sam shook his head. "I'm staying. Dad'll look out for me."

:

With a last hug of encouragement to her eldest, she reassured him."Don't worry, son. I'm sure we can fix this."
"Mom," Dean answered, returning the hug, "what if it can't be fixed?"

"I'd better go," she said, releasing him and making for the open sea, leaving three pairs of eyes staring worriedly after her.

:

:

An arm around his son's chest, giving him support as he treaded water, John let out a sigh.
"Dean, there 's something Mom and I have never told you, not because we didn't want to, simply because we didn't think it was relevant."
He hesitated before continuing. "Here in this pool is where your mom and I first met."

The two boys stared at him, sensing he was going to reveal something important.

"When I first set eyes on her, I'd never seen anything so beautiful. It was love at first sight. And I know it was the same for her, but right from the start there was a huge obstacle to our love.
I know this is gonna come as a shock to you boys, but we never believed we could be together because she was a mermaid and... I... was human."

John felt Dean's body stiffen beneath his arm, and two pairs of eyes stared at him incredulous.

"No, dad! " Dean exclaimed in disbelief. "That can't be."

"Dad, what are you saying?" Sam echoed his brother. "Humans can't change into merpeople."

"No, they can't, " John agreed, "but your mom and I were so determined to have a future together that she resorted to 'unorthodox methods' to allow me to become a merman."

"What kind of methods?" Dean asked, confused.

""I'm not quite sure exactly what she did, though I do know it involved a spell. Some witch she'd heard of who'd done this before for others."

"But magic is bad, " Sam declared swimming to his brother's side and curling his tail around one of Dean's legs. "You think Dean becoming human has something to do with that spell?"

"Who knows," John shrugged. "Maybe my human genes were passed onto Dean and remained dormant until the eve of his Crossover. But I'm only guessing. Perhaps mom will find a better answer."

Dean laid an arm around his brother's slim shoulders. "Does that mean it could happen to Sammy too?" he asked in a distressed voice.

John pulled both his sons into a hug. "I don't know Dean. I just don't know."

:

Even if the weather was warm, the older man knew Dean couldn't stay immersed forever. His son would have to take his first steps on the shore, learn to walk as a new baby does; only he hoped Dean would get the hang of it a lot quicker, he'd have to!

"Dean, I want you to do something for me. It's time to move onto dry land. There's something buried back amid the rocks that you need to go get."

"No, Dad. I don't wanna!" Dean declared.
Sam's no came quickly after his brother's. "We can wait for mom to come back first."

"Listen, kiddo, there's no guarantee she'll find an answer quickly, and in the meantime Dean has to learn how to manage on land. Come on, son. I'll help you as much as I can. Walking on two legs isn't all that difficult. It just takes a little practice."

:

With an unsure nod, Dean swam the few yards to the shore, missing the familiar swish of his tail, but determined to get to grips with this new body.

"Now pull yourself out, rest on your hands and fold your legs up beneath you. You've seen how the turtles crawl with their four. You do the same and head for that rock. Once there, hoist yourself up onto your feet and hold on until you get the hang of standing up"

Dean glanced back dubious at his dad, but followed the instructions, and soon he was balancing upright against the rock wall.
"Good, son. You did real good. Now try putting one leg in front of the other, keeping hold for support."

:

As Sam watched his big brother grapple with the art of human walking, he could feel his eyes filling with tears.
There was no doubt in his mind that Dean would manage to do all he needed to survive on dry land.
His big brother was a quick learner. Thing was, if this couldn't be fixed, he and Dean would never be like they once were. They'd be brothers apart.

:

:

Dean's cry of triumph split the balmy air as he took shaky but ever more confident steps along the gravelly sand.
"That's my boy, " John grinned in pride. "Soon you'll be no different to the humans who were born that way. But now you have to go deeper into the rocks until you come to one which looks like a heart. You'll know it's the right one 'cause it's the only small outcrop around. If you dig down deep, you'll find a bundle wrapped in a waterproof tarpaulin. Bring it back here."

Dean nodded.
His emotions were on overdrive, fear for what had happened, for what might be if his mom couldn't turn him back, of losing his family; yet he also felt the thrill of the unknown.
The merpeople shared the planet with humans but their dry world was out of reach of the water-breathing race.
Now, like his father, he'd get the chance to explore both.

He turned his back on the ocean and following his dad's instructions, he dug out the bag, and tottering a little under its weight, he carried it back to the water's edge.

tbc