"Momma! Momma! Tell me the story again!" cried the voice of the little white earth pony filly with long pale pink mane and tail. She kept bouncing around her mother, a tall -very pregnant- white alicorn with short cropped red mane and tail as she walked slowly down the castle corridor.
"Celestia, would you please slow down a little bit? Mommy is very tired carrying around your baby brother or sister," said Queen Faust as she used her front hoof to gently tap her belly.
They finally reached a large set of double doors that led to a brightly painted bedroom full of stuffed animals, frilly dresses, pink bedspread on a huge alicorn-sized bed and wall of windows that looked out over an east-facing garden. Faust rolled her eyes at the mess around them and lead the filly to the bed, tucking her in for the night.
"Momma... please the story??" little Celestia pleaded. Faust chuckled slightly and nodded as she settled her self on the end of the bed.
[/hr] She ran.
She ran as fast as her tired legs could carry her. The layers of her skirts tangled in her hind legs making her stumble but fear kept her going. Her shoulder length brown mane splayed back behind her like the sparks of the torches carried by her pursuers. Her bare hooves pounded on the thick layer of last autumn’s leaves as she ducked and swerved to avoid the trunks of trees. Her heart pounded profusely in her chest as she ran; her breath coming out in panic-filled gasps and fogging in the cool night air. She may have appeared to be an earth pony but she did not have their stamina or strength and that worried her.
Suddenly, she realized that she could see the trees much more clearly and a quick glance to the east saw the light of pre-dawn. She could still hear the awful evil dogs baying and male voices hollering behind her. She feared looking back and another stumble taking her down. She knew that if that happened, she’d be done for!
As she swerved to her left, she found a dirt road and an arrow sign pointing to the ocean. A flood of relief came over her, knowing she was nearing her destination and her salvation. She still could not fathom how her secret got neither out nor by whom. She only knew that during the party, the guards were eyeing her with extreme concern & whispering to each other. She knew that her time here was at an end. She had strict instructions to return as soon as she got any suspicion of the ponies becoming aware of her story proving false.
She had plenty of information to return to her family. The time was not now to reunite her family with these ponies. They were too single-minded, locked up in their silent stone castles and homes; they were a superstitious lot for her family. And their views on the place of a female (despite their leader being a young mare) would not go over well with her elders, all who were mares of course.
The sun was fully raised by the time she reached the start of the ocean’s beach. She barely paused to take in the view and catch her breath. Instead, she started tearing off the layers of clothes she had been forced into by the servants prior to the party. She discarded each piece as she ran closer and closer to the water’s edge. By the time she reached the lapping water, she had on only the thin white linen petticoat.
A quick glance back told her that they had also exited the forest. Exactly what I want, she thought as she walked into the water.
Barrel deep in the water, her sea shell pendant began a soft glow. The further she walked, the stronger the glow became. By the time she reached neck height, it nearly blinded her. She focused her sight on the ocean in the distance and dared not look back as she heard the male voices raised in anger. A dolphin leaped only a league away and she knew her family waited for her.
She sank.
She sank into the water and the moment her necklace touched the ocean, the transformation overtook her; the petticoat falling away as her beautiful silver-green merpony tail reappeared, as did all of her royal jewelry, crown and the white silk top she favored above all others, draped casually over her chest.
The last thing the stallions on shore saw of the mysterious mare was her petticoat floating on the turning tide and a huge merpony tail flip over on the surface before disappearing in the reflection of the rising sun.
From the top most balcony of the castle a pure white unicorn mare, with beautifully fashioned long red mane and tail and wearing an elegant gown, watched as the tail broke the surface a little further out to sea. She had watched the mare from the point she exited the forest to the point she disappeared into the sea.
"Such a shame," said the mare.
"What is a shame, my lady?" asked the maid-mare behind her.
"Shame I never got that pony's real name," replied the mare as she nodded her head towards the sea. The maid-mare had not seen what the mare had seen and so did not know what to say.
A gruff male voice broke out into the room. "My princess, please. Your guests are all wondering where you've disappeared to," said the unicorn stallion who was her 'Governor' (aka. Jailer).
"Of course, Lord Gold Bar. Please send a messenger to recall that hunting party out yonder at the beach," she said sweetly as she walked past him and returned to the boring party with the boring snotty unicorns of the so-called 'high society' of the time.
[/hr] "That mare at the castle was you, Momma? Right?" Celestia asked excitedly. Faust nodded gently. "It was a very, very long time ago..." she whispered.
"Did you ever get to meet that pony again?" the little princess asked curiously. Faust shook her head sadly. "No... she's never been back since that castle was destroyed in a civil revolt."
"What if she found a way to become a pegasus and came here?" Celestia asked.
"I would welcome her with open hooves; you should know that Celestia. We never turn any pony away... no matter who they are or where they come from." Queen Faust looked down on her sleepy daughter. "Remember that for me, my little princess."
"I'll remember that for you, Momma.... Always."
Author's Note
The italics were the original story I wrote back in 2014. Everything else was written when I posted this, as was the turning the story to pony.
Another short little bit of a story.... I hope it was ok. 
So i'm gonna have to make up some more story to go around the original. 
)