Mercy had always been a curious child. Since the moment she had even a modicum of control over her body she wanted to know what everything felt like. She needed to know about the world. Her wide innocent green eyes wanted to see everything; she wanted an adventure before she could even pronounce her first word.

Her parents had their hands full when she couldn't speak. She cried when left alone, she cried when she had been left in her crib for too long and the worst, she cried just for the sake of crying. It drove the Winchester couple insane; she was so fussy when it came to being alone. But when it came to hunger or a soiled diaper she cried until one parent entered the room and just stared at the expectantly.

Safe to say, she ended up with much more than one rash. Not fun for any of the family.

But it was the moments when her parents played with her and made her laugh that John and Mary understood the joys of parenting. Their child was a pain in the backside but her smile made their hearts swell and made them feel that it was all worth it. It didn't mean that they weren't hoping for their daughter to grow up a little so that they could understand what it was she wanted.

Fortunately their wish partly came true. As Mercy was a curious child she wanted to know everything. So she picked up speaking fairly quickly. Fast enough that the older Winchester's believed that their little Mercy was genius. They were proud of her until she learned the words what, where, why and how.

Why had to be the worst. Whoever had invented the word? They needed to be brought back to life just so the Winchester's could shoot them. It was just plain torture, the constant stream of 'Why?' forced the young couple to realise just how little they knew about the world.

No they didn't know "Why the sky was blue?" nor "Why could you see through glass?"

It was when she started walking that they realised how hard being a parent was. See Mercy gave the couple no time to prepare for her walking by crawling or even bum-shuffling. Mercy went straight from sitting up to using the walls to clumsily walk to the things that caught her attention.

The coffee table had never looked so dangerous before. And the stairs were basically a death trap for little toddlers.

Mercy didn't stop moving until she crashed somewhere vaguely strange. They had found her asleep in the mop bucket once; she was absolutely soaked and was in desperate need of a bath. They just couldn't let the little monster out of their sight. They didn't need a repeat of the hot sauce incident. How she got it in all of John's shoes? They had no idea.

But she was their first child, the best thing that had ever happened to the Winchester's and the source of most laughter and joy. For every first the couple took a picture, her first word "Win" was photographed with her giving the cheesiest grin anyone had seen on a baby. John couldn't shut up on how she was destined to win and would be the best of the best.

They doted on the girl and gave her all she could ever need. But weren't scared to tell her off if she was close to hurting herself or did something wrong. She was already showing to be a strong willed child but had a strange kindness that lead her to give her parents giant hugs whenever they were feeling even slightly sad.

She grew like a weed and the years flew by until her fourth birthday, when she was asked if she wanted a sibling.

"I want a sister!" Was the instant response, her hands pointing at her mother's stomach.

Mary and John chuckled, the father picked up his daughter making sure her yellow dress didn't lift to show more than necessary. Her chocolate hair put up into pigtails with blue ribbons, John refusing to let his daughter live in a pink wonderland. He knew they would all get sick of the colour if he had let his daughter to become obsessed with it.

"Sorry kiddo, we don't get to choose. Just like we didn't get to choose if you were a girl or a boy, but we would love you no matter what you were. So you have to do the same for your little brother or sister okay?"

"What if she is a meanie? I don't like meanies!" the young girl shook her head violently, entirely against having to have a mean little sister.

"Don't worry baby." Mary soothed, "As the big sister you have to teach them to not be a meanie."

"Yeah, with you on the case, we have nothing to worry about!" John joined in. Both adults holding back their laughter and hoping to get the child to agree with the thought of a little sibling, they expected she would agree.

Mercy was constantly trying to keep her parents happy and helping them in any way possible. They wanted their daughter to be happy, but she didn't seem happy until her favourite people were too. A sibling would help with that, someone she could teach and look after.

It helped that they had been planning for another child for a while. Mercy was such a joy to have that they wanted another one, but John had put his foot down at three at the most. They just didn't have the income even with John co-owning a garage business and Mary being the manager of the diner.

"I'll be the best big sister ever!" The small Winchester yelled. She didn't stop babbling about what she was going to teach her little sister and what life was going to be like.

Mercy once again poked her mother's protruding stomach. It had been around five months since Mercy's birthday in April and the news of a new Winchester, Mercy had been doing everything she could to help her parents and asked as many people she had contact with for information on how to be a good big sister.

It had caused some embarrassment to the older Winchester's when she asked the couple of bouncers from a nearby club when they were eating in the diner Mary worked at. They were large men, muscles covering head to toe. One looked like a stereotypical American with blonde hair and blue eyes, whilst the other was told by Mercy he had,

"Really pretty dark skin. I like dark colours, because daddy's hair is dark and so is mine!"

Luckily the man hadn't been offended in the least and even gave the small girl tips on how to look after little brothers. The man had a little brother and knew exactly what to say to the wide eyed girl.

Mercy furrowed her eyebrows at her mum's tummy, she just didn't understand. How did a baby fit in there? Was she in there when she was a baby?

"Can she come out yet?" Mercy asked. Her eyes never straying from what she knew was holding her little sister.

"No baby, your little sibling needs time to grow before they can come out into the world. Would you like it if someone woke you up and pulled you out of a very comfy bed before you had a proper good night's sleep?"

The small girl looked at her mother with frightened eyes before hugging the bump.

"Sorry, I didn't know it was like that. I'll wait for you, so don't worry!"

Mary watched her child's antics with a fond smile, it was a blessing when Mercy grew older, and she started loving sleep more than her mother. Which was impressive but it was much easier on the couple. However, they were not looking forward to when she started school and can't wake her up to go.

"That's my baby girl. Now how about we get you to bed hmm? We've got a busy day tomorrow; we're going to see Connah. His mum said he missed you very much and I know how much you love playing hide and seek with him."

"Okay, Mummy."

"Remember sweetie, the angels are watching over you."

Mercy was very confused. She knew it was almost time for her little sister to arrive, but why did her mummy yell at daddy that her water broke. It made no sense. Water doesn't break, it just dribbles and splashes.

But it was very scary sitting in the back of their car whilst her mummy was making sad sounds. She was crying and groaning, her mummy wasn't allowed to cry. She was meant to make her mummy happy, but it wasn't working.

Her daddy had yelled at her to be quiet when she tried to talk to her mummy. All she was told was that her little sister was going to be born soon. But that made no sense!

Mercy thought that when her little sister was born everyone would be happy. They weren't supposed to be upset! She was so confused, she really wanted to cry. But her mummy was crying, she couldn't cry now. Maybe later, maybe she would be allowed to cry later.

Mercy could only do one thing, the one thing that her mummy did for her when she was sad. She sang "Hey Jude".

She couldn't remember every word and her voice would waver and crack but it looked like it was helping her mummy stop crying. Mercy wasn't going to stop singing until her mummy was smiling again and her daddy wasn't mad anymore.

She'd sing until her throat hurt like that time she yelled for too long, until it felt dry and burning. She'd sing until she couldn't sing anymore.

She didn't stop singing when they took her mummy away from her in the hospital and left her with daddy. She kept singing even when everyone in the waiting room stared at her. She had to keep singing for her family, because she had to make sure her family was happy. She didn't even care if she had a little brother instead of a little sister like she wanted.

She just wanted her family. She wanted to know what they were doing to mummy and her little sibling. But she couldn't cry, she couldn't ask any questions, her mouth only let her sing.

She wasn't sure when she fell asleep, but she woke up to her daddy's voice rumbling in his chest. He was talking to someone next to them, he sounded like an old man. But all men were old in a child's mind so it wasn't a very accurate deduction.

"She sings beautifully, you should be proud of her."

"Don't worry. I'll always be proud of her. She's my first born you know. Bit of a spit fire though."

Daddy sounded tired and worried. Was mummy still not feeling better?

"Really, I'm sorry for asking. But why did she keep singing until she passed out? It's not something most children do."

"Ah, it's the song her mum sings her whenever she doesn't feel well. My wife just went into labour and Mercy didn't really understand what was happening."

He shifted slightly to let Mercy settle more comfortably. He slowly stroke his daughters hair in hope the she would be calmer when she awoke.

"So she was singing to make her mum feel better huh? That's one smart cookie you got there. Iron will too apparently. Her name's Mercy? It's a very unusual name, any reason for it?"

"It was unique and had the qualities we hoped she would have. To have strength and kindness, of which she has in bounds. We were so lucky to have her; she made our lives so much brighter."

"Hmm, and this next child your wife is having now?"

"She wants to call them Dean or Deanna depending on the gender. After her mother that died quite a few years ago. But Mercy here is determined to have a little sister."

"I fear what that babe will have to go through in the future if they turn out to be a boy."

"Trust me. You really don't want to know. She has my stubbornness and her mother's patience and determination, a very deadly combination inside an energetic little girl."

Before the stranger could once again speak, Mercy sat up having had enough of the conversation.

"Mr Winchester?!" a nurse called. John swiftly made his way towards said nurse with Mercy securely in his arms.

"How is she? Any complications?" he sighed at the negative reply. It was a relief to know that his wife and new child were fine.

"Daddy?" the small voice made John cringe. He was supposed to look after his daughter but only succeeded in worrying her.

"Hey, kiddo, are you ready to meet the new family member?" It took a few seconds for the sentence to process in her mind before everything just flung itself out of the window.

"Yes! I really wanna see! I'll be the best big sister ever!"

John stared wide eyed before shrugging it off. Kids were more durable than most adults think and could bounce back so easily.

Now it was time to meet the new part of the family.