Bigger, Not Older.

Twilight Velvet, and her husband, Night Light, stepped out of the cab parked in front of their home in Canterlot.

"That was a wonderful vacation," she said, remarking on the romantic weekend away with him.

"I know. I can't wait to tell Twilight the big news about her new..." he trailed off as they neared the door. A cardboard box labeled Canterlot Home for Wayward Foals sat empty on the stoop. He looked to the left and right on the road, looking for a wandering foal, and rushed toward the door, along with his wife. He unlocked the door and burst inside, "Twilight!" he bellowed into the house. But he didn't have to go far. There before him was his daughter, wearing a familiar leather mask and saddle. A white colt rutting her silly from behind. The whole house reeked of sex.

"Mom! Dad!" Twilight greeted cheerfully as she peeled off the mask. "This is my new brother, Shining Armor!" He dismounted her without ceremony and trotted over to them, his cock flopping freely beneath him.

"Mom!" he greeted. He reared up and gave her a kiss.

On the lips.

With his tongue.

"Oh my goodness!" Velvet scoffed and shoved him away.

"What in Equestria is going on here!?" Night Light fumed.

"It's okay Daddy, I read about it in a book!" Twilight explained. Shining trotted around behind Velvet to show her that he loved her with a 'special mare kiss'.

"EEEK!" Velvet shrieked.

~~~~~~~~~~~~~~~~~~~

After a very long, frank, and awkward discussion, Velvet and Night Light each explained to them, in exhaustive detail, why what they were doing was wrong.

"That is just simply not how you behave with your brother!" Velvet told Twilight.

"Or your sister!" Night Light scolded Shining. "And certainly not your Mother or I!" he said to both of them.

They went on to explain the importance of a pony's personal privacy, and how she shouldn't be going into her parent's room, or closet. And that certain thing were only for when a pony was older.

"You see, dear?" Velvet told her daughter, "This is what we mean when we say that you're too smart for your own good. You're lucky that you weren't in season!"

"Okay," Twilight and Shining resigned, promising to not do those naughty things anymore. Shining was retrained on how to interact with ponies and show affection in an appropriate, socially-acceptable way to family members. And all was well.

~~~~~~~~~~~~~~~

"Hey Shining?" Twilight whispered into the darkness of the bedroom that night. Shining looked toward the sound her voice in the doorway. "Want a 'special stallion kiss'?" she asked. He smiled knowingly and lifted his blankets, silently inviting her into his bed.

"Hey Twilight," Prince Shining Armor whispered. Princess Twilight Sparkle looked toward the sound of his voice in the doorway of her Canterlot Castle suite. It was the night of his twenty seventh birthday. "Want a 'special mare kiss'?" he asked.

She smiled knowingly and lifted her blankets, silently inviting him into her bed.

Just as she had for all these years.

The End

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