Their undersea home was far from land, their now human member unable to reach the shore-line under his own power.
Dean held on to his parents as they carried him speedily along, their meta the rocky pool where Mary had first encountered John.
Once Dean would've been able to swim the distance in record time but it was no longer so, handicapped by a body ill-suited to the seas.
As they sped through the water, each was caught up in their own thoughts.
Mary was concentrated on how to fix this, knowing the only way was to go back to Janara and beg for her help. There HAD to be something the water-witch could do, some way of reversing the curse.
John on the other hand, mused at the irony of what had happened to his first-born.
He himself had been ecstatic at becoming a merman and being able to join his love beneath the oceans, yet here was Dean, undergoing the opposite transformation.
The question being why? What was the cause? Was it his fault? Had John infringed some taboo when he'd been turned into a merman? Was his son paying the price?
The sins of the fathers......?
All Sam could think of was that his big brother had almost died, and he'd been so scared.
Now he was going to be taken from him, not by death, but by some freak accident which had given him legs instead of the tail Dean had been so proud of.
They had to find a cure, or he and his sibling could never again race each other under the waves, nor share their sleeping space, nor do any of the things they loved doing together.
But, Sam vowed fiercely, that wasn't an option, because if he had to, he'd search the seven seas to find a cure for his big brother.
Holding onto his parents as they chewed up the sea-miles, Dean was completely distraught.
He was freaked by the difference in his lower body, the legs weak in comparison to his solid, muscular tail.
Why had this happened to him? How could his perfect world have fallen apart in a split-second?
He'd been so geared up for his Crossover party, his entry into adulthood, when his sexual organs would come into maturity and he'd be respected as a full merman, no longer regarded as a child.
Now none of that would happen.
Dean knew where they were going.
He'd been to the deep pool; swimming that far was a 'do or dare' among the younger merkids. What Dean didn't know was that his dad had been a human before marrying his mom and that very pool was where they'd first met.
Mary and John had discussed the matter, and decided not to tell their sons. What was the point? It would only have generated needless curiosity on Sam and Dean's part.
Truly the only ones who did know, other than the water-witch, were Mary's mother and father, and they'd preferred not to say anything to their friends and relatives.
Humans weren't exactly welcome in the Merworld.
The Merpeople had been witness to many examples of their cruelty towards the large seas creatures throughout the centuries, to be particularly well-disposed towards them.
No, a fictional story of John having come from a far-off clan of mermen was given when anyone asked how he and Mary had met.
In the distance, the shore-line came into view, but its sight merely made the little family feel even worse.
What were they going to do once they'd reached the pool? How could they leave Dean there on his own? He was only twelve, he needed his parents and they needed him.
Four pairs of eyes gazed at the overhanging rocks with trepidation.
“Mom, dad,” Dean murmured. “What's gonna happen to me?”
“Hey, hey,“ John broke in. “Nothing's gonna happen, kiddo. This is just a momentary glitch. We'll figure this out. We're not gonna leave you. Your mom or I will be hanging here in the pool until we think this through.”
“What's there to think about?” Sam broke in, eyes tearful.“How can we leave Dean here on his own? You have to find a way of changing him back.”
“We will,” Mary said. “But for now Dean has to stay on dry land. He'll die if he comes back home with us.”
Sam threw himself onto his brother. “I'm not leaving Dean,” he said stubbornly. “I'm gonna camp out here in the pool until he can come back with me!”
But John wasn't sure things would pan out as Sam wished.
It was fine to hope, but it might be that Dean would have to say good-bye to the seas for a much longer time.