Sweetie Belle was completly unaware that anything was wrong. She was upstairs playing with her doll set, happily ignoring the world around and playing pretend. Little did she know that in a matter of minutes everything would change.
It very nearly broke Rarity's heart seeing her "little sister" so happy and carefree. She very nearly felt compelled to just leave Sweetie Belle alone and not break the news to her but she knew she would have to do this sooner or later. Taking a deep breath she opened the door slightly. "Sweetie Belle?" she called gently, trying not to give her "little sister" any reason to be worried.
"Rarity?" Sweetie Belle asked. She put down the dolls and turned towards the door.
"We have to talk about something." Rarity said, opening the door further and entering the room.
"Is something wrong sis?" Sweetie Belle asked. She never did like seeing her big sister unhappy.
Rarity paused, unsure of how to proceed. After looking around, just to ensure that no one else could overhear her she sighed and took a deep breath. "Have you ever wondered where you came from?" she asked Sweetie Belle.
"Well, yeah. At least I think so." Sweetie Belle said.
"Did Mom and Dad ever tell you anything?" Rarity asked. She was trying her best to tiptoe around the subject, hoping to avoid what she knew was inevitable.
"No." Sweetie Belle said "They just told me that I was a special case whenever I asked."
"Well you're probably not going to believe this but you're not actually a human being." Rarity said.
"What you do mean I'm not human?" Sweetie Belle asked "I have emotions and I can think and feel. Though whenever I take a bath the water always makes me feel funny."
"I know this is probably going to sound weird but you're a robot." Rarity said "That's why water has always made you feel funny."
"But I can't be a robot." Sweetie Belle said "I don't sound like a robot or feel like a robot."
"I know that Sweetie Belle." Rarity said "But it's the truth. I have a letter to prove it." She proceeded to show Sweetie Belle the letter she had recently received.
Sweetie Belle read it, but she still couldn't believe it. It couldn't be true, there was no way. How could she possibly be a robot and have all these emotions? Didn't Miss. Cheerilee teach her that robots could not think or feel on their own? How could she be a robot and yet be capable of thinking on her own?
"You still don't believe me do you?" Rarity asked.
"Yes." Sweetie Belle said "This is all some kind of joke isn't it? This is your way of getting back at me for putting dye in your hair shampoo."
Rarity sighed once again. She had expected Sweetie Belle to deny all of this. She was certain she could find a way to reveal the truth to Sweetie Belle but she didn't want to do anything that might inflict more emotional trauma on her "little sister". Reluctantly she decided to admit it was a lost cause. "I'm sorry Sweetie Belle." she said "I guess there's no way to convince you. Perhaps I'm wrong after all." and she left the room.
Sweetie Belle tried to play with her dolls again but she found that she just couldn't get into it. She put the dolls away and went downstairs. She was so distracted that she didn't notice Opal, who was lying at the bottom of the staircase and stepped right on her tail.
Opal hissed and swiped her claws at Sweetie Belle who raised an arm to defend herself. Sweetie Belle screamed and Rarity came running. Using her magic she pulled Opal away before she could do any more harm. "Are you alright Sweetie Belle?" Rarity asked.
Sweetie Belle didn't respond, she was too busy looking at the scratch marks on her arm and gasped as did Rarity. Instead of drawing blood the marks revealed wires of various colors. Rarity had been right all along. "I really am a robot." Sweetie Belle said to herself.