Chapter 1
The day started out like any day. Rarity got up, fed her cat, woke up her little sister, and while her sister was at school, worked on a fashion design. It was when Rarity picked up Sweetie Belle to go home did it happen. She walked to her school to see her sister waiting in front. Sweetie automatically ran up and said, "What took you so long?"
"I'm sorry, Sweetie. I was very busy." But just then, two fillies, a pink filly and a silver filly, walked up to Sweetie Belle.
"They must be those two mean fillies Sweetie tells me about. Just look at the expressions on their faces!" And of course, they did both have a smirk on their faces.
"Hi there, Sweetie! I hope to see you tomorrow!" the pink filly said, who Rarity presumed to be Diamond Tiara due to her cutie mark.
"Go away, Diamond and Silver." Sweetie groaned. Diamond then looked up at Rarity.
"By the way, is that your big sister or your mother, because she looks to old to be your big sister!" She said as she and her friend sashayed away laughing. Rarity watched them in horror. Sweetie noticed and said,
"Don't take it personally. They always act like that." But Rarity still didn't move. She then turned and trotted in one direction.
"Come on, Sweetie." She said.
"But home is that way!" Sweetie said,pointing her hoof in the opposite direction.
"We are not going home. We are going to Twilight's, to see if she has anything to make me younger." Rarity said.
"But you're only 25!" Sweetie cried as they walked towards Twilight's house.
"Your classmates are right, even at that age I'm getting old. And look, we are already here!" They went to the door of Twilight's castle and knocked. Twilight opened the door and welcomed her friends in.
"What can I do for you?" She asked.
"Twilight, I need something that will make me younger."
"But you're only 25."
"I know, but a filly today called me old."
"Was that pony, by any chance, Diamond Tiara?"
"I think so." Twilight sighed.
"If you insist." She then went to her cabinet and pulled out a sack of red berries. "These are youth berries. With everyone you take, you will become younger by one year. It affects you in thirty seconds from taking it." Rarity grabbed the bag quickly and ran home with Sweetie. She hurriedly went to her table and opened the bag.
"Are you sure this is a good idea?" 
Sweetie asked. Without responding, Rarity quickly ate one. Then she ate another. And another. And another. Soon, she had quickly eaten all the pills. She looked at Sweetie and said, "How many pills were there?"
"20."
"And I'm 25, which means, oh no...." It had already been 20 seconds! 10...9....8.....7.......6.......5......4......3......2.....1! Then all of a sudden, she began to shrink, and as she shrunk, her cutie mark vanished from her flank and her features became more foal like. And when it was over, Sweetie saw not the older sister she knew, but a filly that was exactly her age.