AN: This is finished. It has 13 chapters in total, and I will be uploading it weekly on Monday.
Warning: This is not a female-Harry fan fiction! Neither Diana nor Heidi are female versions of Harry! They might be Harry's sisters in some alternative universe, but none of them is Harry's female version!
Disclaim: I don't own anything (except maybe for Diana and Heidi)! This all belongs to J.K. Rowling, but you already know that, so why am I still boring you with this? I have no idea.
Chapter 1: The Girls Who Lived
The Boy Who Lived never existed, because on the night of 31 July 1980, Lily Potter gave birth to two beautiful girls instead. The girls were names Heidi Rosalie Potter and Diana Lillian Potter. They were the most unusual pair of twins that existed, mostly because you could tell them apart quite easily: Heidi had brilliant-green eyes just like her mother and James dark hair color while Diana had her mother's vivid-red hair and her father's hazel eyes. Heidi was into sports and loved reading while Diana was a more girly type of girl who enjoyed gossips and had an unusual obsession for animals that preoccupied her parents quit a lot.
But that was not the real reason that concerned the headmaster Albus Dumbledore at the moment, though it could be listed among them. The biggest concern he had at the moment was the prophecy that had been made barely a few weeks before the twin girls and young Neville's birth, the prophecy that concerned the most feared Dark Lord of all times and a child that was supposed to be born at the end of the 7th month. He hadn't really known which child it was referring to, the Potters or the Longbottoms, until the twins had been born.
Now he was convinced that the prophesy was speaking of the Longbottom boy, because the prophesy clearly stated that it was a "one with the power to vanquish the - Dark Lord", not two. So he deemed the Potter children safe from the Dark Lord and only sent in hiding the Longbottom couple together with their new born son Neville.
Imagine his surprise when the Potters were found dead in their house on Halloween night and the Dark Lord had apparently lost his powers…
The only mark that the Dark Lord left behind were two identical lightning bolt scars on the twin's foreheads, Heidi's was just above the right eye while Diana's was just above the left, alas another thing to distinguish them by. No one knew what really happened that fateful night, just that the Dark Lord had vanished for good.
As for the twins, they were sent to live with their only living relatives the Dursleys.
Petunia and Vernon Dursley were one of the most common and anti-magic muggles you could find, still Dumbledore deemed it safe to leave the girls in their hands, on account that their godfather Sirius Black had been charged with first degree murder and suspected to be a Death Eater and therefore couldn't take custody of them.
But the girls didn't have the harsh life that Minerva McGonagall thought they'd have, far from it.
Petunia, who had indeed hated Lily for being special, had only one thing that she wanted more then to be a witch (because there was no denying it she hated her sister because Lily was a witch and she was not), and that was to have a girl. So, imagine her surprise when she found the two cute little girls at her doorstep when she went to take out the bottles of milk. She had been confused of course, and more then a little angry with this Dumbledore guy who thought he could just solve everything by writing a stupid letter where he informed her, in a much to formal manor in her opinion, about her beloved sister's death and leave all responsibility of raising the two girls on her and her husband's shoulders, the nerve of some people!
She had made a decision that day. She would raise the girls, but never (if it was possible) ever mention her sister, or her sister's husband or the world in which their real parents lived in for the matter.
------
"Oh, come one! What's so frightening about big D!" whined a beautiful red headed girl.
"He'd kill me Diana!" shrieked a small and thin boy with brown hair and blue eyes.
"Ah-ah, you're such a wuss, it's no wonder Dudley can boss you around," Diana sighed just as she heard a shout from behind.
"Hey, big D! I found your sister!"
The boy that was by her side gave a frightening squeak and dashed out of sight faster then one would think was possible for someone so small. A couple of seconds later a chubby blond boy with narrowed blue eyes and clenched fists came around the corner surrounded by 3 equally round boys.
"Where is he!" he demanded the moment he was a few strides away from Diana.
A vein burst inside the pretty girl's head and she turned around to face Dudley and proceeded to hit him with her fists. "How should I know, he ran off the moment he heard your lackey calling you! Seriously D if you dare as much as speak to me in the next 24 hours I'll strangle you!" She gave on last hard punch to emphasize her point and then scurried off to find her sister.
"Don't worry D, she'll com around," one of his friends patted him sympathetically on the shoulder.
"Yeah," Dudley said bitterly. "Let's go and find that kid."
There was a murmur of agreement and the kids headed in the opposite direction in which Diana had.
Diana ran as fast as she could up until she intentionally slammed into the back of an identical girl with dark hair and vivid green eyes.
"Hey! What happened, did big D ruin another one of your dates?"
"I hate him," Diana swore vehemently.
The ember eyed girl burst into fits of laughter. "I know, I know, I would too. But he means well."
That burst another vein in the red haired girl's head. "Mean's well! MEANS WELL! SO NOW RUINING MY LIFE MEANS WELL TO YOU HA!!!"
"No, wait, I didn't mean that!" Heidi tried to pacify Diana before the girl went and took out her furry on her.
"I hope you didn't, because if you did…" she glared threateningly at Heidi.
"Anyway, we should head home," Heidi said urgently. "Mom's making cake, remember?"
All traces of anger seemed to vanished miraculously from the red haired girl's face at the mention of sweets and she quickly agreed. "Yes, yes, let's go home!"
Heidi sighed in relief and started walking towards nr 4 Privet Drive. It wasn't a long walk as the house was close to the playground that the kids of the neighborhood usually hang around, just a few strides down the road, a left turn and the third house across the street was where the Dursley's lived.
It was a neat and tidy house, with a perfectly mowed lawn and a beautiful flower bead. The interior was just as sparkling clean and the smell of fresh baked sweets was poring from the kitchen.
"Hi mom," Diana waltzed into the kitchen through the back door and kissed Petunia on the cheek.
"Hello muffin." Petunia smiled lovingly at the girl. "Where's your sister?"
"Right here," Heidi came into view and kissed her mother. "Hi mom, need any help?"
"Oh, that would be lovely dear. Can you set the table for me?"
"Sure!" Heidi made her way to the drawer and pulled out 5 plates.
"Watcher making?" Diana asked while bending her nose low to sniff the sweet aroma of her mothers cooking.
"Roast chicken with lemon and rosemary roast potatoes."
"No sweets?" Diana asked disappointed.
"Remember what we talked about pumpkin, no sweets until tomorrow! You'll have plenty to eat at Dudley's birthday."
"Ah, not even a bonbon?"
"Absolutely not! I can't risk it with you kids anymore, the last time you ended up feeling sick for days, and god knows you kids need to lay of those sweets. Now why don't you help me take these dishes to the table your dad will be home soon?" Petunia handed Diana a plate with salad and another with fried sausages, then proceeded to take out the roast chicken.
"You know she's right," scolded Heidi, a wide grin spread on her cute face. "You need to lay off the sweets."
"Traitor!" Diana stuck out her tongue.
Just then Dudley entered through the back door looking positively exhausted.
"Dudders, what happened to you?" Petunia asked concerned.
"I couldn't catch somebody." Diana smirked cheekily at him. "But I will eventually!" Dudley promised and Diana sent him a death-glare.
Petunia, sensing the beginning of another on of the infamous shouting matches between the two kids, quickly tried to change the subject. "Where would you like to go for your birthday Duddikins?"
The mood instantly brightened as Dudley said: "The zoo!" He looked questionably at Diana and Heidi.
While Heidi nodded her consent, Diana whined saying "We've already been at the zoo trice! It's not gonna get any interesting now. Let's go swimming!"
"I can't swim!" Dudley whined.
"I'll teach you," Diana said and put on the puppy-dog-face that no member in the family had ever been known to refuse.
"Alright," Dudley gave in. "But you'd better keep your word!"
"Of course I will!"
The sound of a car coming to a halt in front of the house could be heard and Diana gave a squeak of delight and bounced toward the door. "Daddy's home!" She knocked head firs into Vernon's round form and hugged him as much as her short hands would allow her.
"Oh, hello there prince, I see you are as energetic as ever." Vernon patted her on the head and picked her up in his arms.
"I talked to Dudley, and we both agreed to go swimming tomorrow!"
"You don't say," Vernon entered the kitchen and put Diana down on the first free chair he could find. "Good evening family," he greeted. "Mmm, roast chicken, my favorite."
"But no sweets!" Diana pouted and everybody except Dudley laughed.
"You really should lay off princess," Vernon commented lazily and began digging in his food.
"Dad!" Diana started to complain but Petunia cut her off.
"Eat your dinner muffin before it gets cold. You'll get plenty of sweets tomorrow."
The next day the Dursley family woke quite early because Vernon wanted to teach the kids how to fish.
The kids were ready to go in less then 30 minutes and the Dursley's were on their way towards a one way trip of fun an relaxation, the post hadn't even arrived yet.
The fishing trip proved to be quite difficult for the family however, because Diana couldn't stand to see the cruel way in which the poor worms were treated and so they had to cut it short and head to the beach.
The rest of the day was as normal a day as could ever be; nothing unusual happened to forewarn the Dursleys that this day precisely could be any different then any other.
But, as they returned home tired and sleepy, with Diana and Dudley bickering about some random boy they had met, Heidi and Petunia debating what to cook for tomorrow morning; it was then, after he opened the front door of his normal house and searching through his normal mail, that he saw them: 2 abnormal letters written in green ink with a green sigil that was shaped like a badger, a serpent, a lion and an eagle surrounding the letter H…