Disclaimer: I do not own Harry Potter or any locations, characters, or ideas from the books, movies, or games. I am merely borrowing them. I am making no money from their use. I use moments from the books to parallel the story, I do not do this to plagiarize. Any words taken from the books, movies, or games is done so with respect and I claim none of it as my own.

I do however claim the character Katrina Lillian Potter, and any other original characters or ideas introduced in this story.

AN:

Hey everyone! Welcome old readers who are returning with me to the world of One Difference Is All It Takes and new readers who probably have no idea what I mean by returning. As promised in my last update to the original version of this I have rewritten the story. With the rewrite come things have changed and others stayed the same. I will post all of the chapters containing to points in the story I had already reached in the original as I have finished rewriting them. After the rewritten parts are posted I will post new chapters as I finish them. I would post an update schedule but as anyone who has ever read any of my stories is well aware, I suck at keeping to those schedules life just gets in the way too much. I promise to post as often as I can though.

If anyone has any suggestions for something for the story feel free to review or pm me about it, I'm always open to hearing suggestions. I will try to respond to any reviews I get when I can. Now let's put an end to this rambling, on with the story!

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July 31st, 1980 – St Mungo's Hospital

Sirius Black was a brave young man, a man who would never admit he was scared. But today was probably one of the scariest days of his life, and he wasn't even the one having a baby. No his best friend, his brother James Potter was about to become a father. Lily his wife was in labor and had been for four hours. Sirius, Remus, and Peter had been pacing around the waiting room since they'd received the floo call from James just after dinner.

Remus Lupin was just as worried as Sirius although he'd easily admit it. The young werewolf was terrified of losing his friend. The marauders would not survive the loss of Lily or the baby and Remus knew the odds better than any of his friends. With magic the odds where so much less, but it didn't calm his own nerves much.

Peter Pettigrew would never admit he didn't really care about the baby being born. Honestly he'd rather be home eating or sleeping, not sitting in an uncomfortable hospital chair. But to keep up his act he had to act worried, nervous. He was but not for the baby, he was more worried about his longtime friends seeing his left forearm or his master calling at the wrong moment as this was taking far too long.

"People for the Potter's?" A nurse calls coming into the waiting room. All three men jump to their feet rushing over. "They will see you now, follow me." The young woman leads them down a few hallways to a room. Entering the room they can see James standing beside a bed, Lily's red mane vibrant against the stark white pillows, in her arms was a blue bundle.

"It's a boy?" Sirius asks running over to the bed with a giant grin.

"Yes and a girl." James laughs turning to look at him, the pink bundle in his arms viewable now.

"Twins? Congratulations!" Remus laughs happily clapping James on the back softly, peering down at the little baby girl in his arms. Large emerald green eyes stare back at him. A tuff of brown hair with a tint of red to it sticks out from her little head.

"Double the trouble." Peter adds with a laugh nudging James in the side jokingly.

"You know it." James grins widely at his friends.

"So what are their names?" Sirius asks leaning over Lily to peer at the little boy in her arms.

"Harry James Potter, our oldest." Lily says smiling at the sleeping boy.

"And Katrina Lillian Potter, our little surprise." James says kissing the baby girl on the forehead, a loving grin spreading on his face as her little hand breaks free from the swaddle and whacks him in the face softly.

"We want to ask you something, Sirius." Lily speaks up catching James' eye.

"We want you to be their godfather?" Sirius' eyes widen as he looks between the two.

"You're serious?"

"Nah that would be you my friend." James laughs, using Sirius' favorite jokes on him.

"Of course I'll be their godfather!" Sirius says a little too loudly, Harry wakes with a start his little face scrunching up and a loud wail echoing out through the room, quickly joined by his sister. "Sorry!" Sirius turns a deep shade of red his grey eyes wide.

"It's okay." Lily waves him off, quickly comforting her son, his little cries fading as he drifts back to sleep. Katrina quickly falls asleep as well as her father shushes her cuddling her close to his chest.

"We were going to make you Katrina's godfather, Remus. But the nurse informed us that it's not legal with your condition." Lily adds smiling softly at her friend.

"Well thank you for even considering it." Remus grins at her. James turns carefully handing the pink bundle to Remus while Lily hands the blue to Sirius, the group stand together for hours each taking turns holding the two newest members of their little family.

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The little family would only get a year together before tragedy would strike. On October 31st, 1981 Lord Voldemort would attack the Potter cottage in Godric's Hollow. James and Lily would die defending their children. Their sacrifice would change the wizarding would forever as the power of their love would protect their children as the monster of a man raised his wand to cast one final killing curse on the two toddlers huddled together in their crib. The green light would leave the two with damaged eyes, and matching lightning bolt scars across their foreheads, but they would survive. The spell would backfire destroying Voldemort's body and sending his soul fleeing into the night.

The twins had done the impossible; they had survived the killing curse. Rubeus Hagrid would take the children from Sirius that night, the marauder too late to save his friends having pulled them from the rubble that had once been their nursery. Sirius Black would be blamed for betraying the Potters and killing Peter Pettigrew along with twelve muggles later that night. He would receive no trial, being taken directly to Azkaban.

Hagrid using Sirius' flying motorbike would bring the twins to surrey, to number four privet drive. Where he would meet with Professor McGonagall and Professor Dumbledore. The twins would be left on the steps of their Aunt Petunia's house with a simple note explaining what had happened to their parents. This is where they would spend the next ten years of their lives, hidden away from the wizarding would that worshipped them.

A breeze ruffled the neat hedges of Privet Drive, which lay silent and tidy under the inky sky, the very last place you would expect astonishing things to happen. Harry Potter rolled over inside his blankets without waking up. One small hand reaching for his sisters beside him; Katrina Potter grasped her brothers hand her other closed on the letter between them. The twins slept on, not knowing they were special, not knowing they were famous, not knowing they would be woken in a few hours' time by Mrs. Dursley's scream as she opened the front door to put out the milk bottles, nor that they would spend the next few weeks being prodded and pinched by their cousin Dudley. . . . They couldn't know that at this very moment, people meeting in secret all over the country were holding up their glasses and saying in hushed voices: "To Harry and Katrina Potter – the twins who lived!"

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AN:

This is shorter as it is the preface to the story. The first few chapters will likely be shorter then chapters later on as they are based off the original version of this story I wrote in the summer of 2016. Those chapters where shorter so, so are these as they are rewritten/ edited versions of them.

I hope you all enjoyed, please leave a review with what you thought and any ideas you may have. But please no flames. I am fine with constructive criticism; but please leave it in a polite manner. Simply calling out ways in which my writing style is either not like yours, or that something is not what most would consider grammatically correct because you dislike it is not helpful. Pointing out ways in which you believe I may be able to improve, either grammatically, spelling wise, or even in style can be helpful. Also if a tense is wrong please point it out, this is a rewrite and I changed the tense when I edited/ rewrote it and there are probably at least a few errors I missed. There is no need to be rude and if you simply don't like the story it is your choice whether you read it or not, so simply choose not to, I don't need to hear that you hate it.

~ Kat