A/N: Here we are! My first ever Harry Potter fanfiction. It has been a while since I got into Harry Potter and am excited to present you with this OC/SI-Insert.

Happy Reading! OWO

The Cousin Conspiracy

Chapter 1

She came into the world gasping and trembling. How could she be alive? At least, she should be in the hospital.

Looking around, everything was wrong. She was not in the hospital like she should be, but in a bedroom. It looked like it came out of the Victorian era with its intricate emerald tapestries. She laid in a king sized bed, making her feel small with how little she took up.

At the same time, everything was familiar. It was her bedroom for the past 15 years which made no sense. An orphan girl like her could never have afforded such luxuries.

Suddenly, someone grabbed her hand, causing her to flinch.

"It's okay, Lobelia. You just had a nightmare,"

That was not her name, but at the same time, it was. Lobelia's head ached. It was as if two people were fighting for dominance in her head.

The elderly woman who took her hand sat in a bergère chair. Despite her tight grip, it seemed like she could be blown away by a slight gust of wind. Her long peppered hair was pulled into a tight bun and wrinkled face was marred with frown lines. She wore strange robes underneath her mulberry shawl.

Great Grandma Monarda, panged in Lobelia's mind.

"What happened?" she asked, her voice horace.

Monarda's dark eyes flickered with worry.

"You caught a bad case of dragon pox," she said, giving Lobelia's hand a soft squeeze. "Even with the dragon pox cure I brewed, there was a large chance you would not survive like your grandfather,"

That's not a real disease, Lobelia thought before sneezing. Bright sparks came out of her nose which burned her nostrils. That was not supposed to happen.

Monarda poured Lobelia a glass of ice water from the pitcher on the mahogany side table.

"Here,"

Lobelia was feeling a bit parched. She gingerly took the glass and was about to drink it only for Monarda to push it up her nose. This caused Lobelia to choke up the water and splash it all over her covers.

"What was that for?" Lobelia coughed.

"That water was not for you to drink. One of the treatments for dragon pox is to submerge your nose into ice water,"

Monarda took out her wand and with a wave, Lobelia's comforters were dry.

Lobelia gaped.

Magic?!

Monarda put her wand away and handed Lobelia another glass of ice water. Lobelia took the glass and submerged her nose into the ice water. The coolness of the water lessened the burning in her nose.

Lobelia asked, "How long should I do this for?"

"For about 10 minutes," Monarda said, getting up from her chair. "I will be right back,"

Before Monarda left, she shouted, "Baldric!"

With a puff of smoke, a house elf appeared in front of her great grandmother. Lobelia stared at the elf. He looked exactly like Dobby with his bat-shaped ears and beady yellow eyes. He was even wearing a grass green pillowcase.

"Yes, Master Monarda?" he asked, bowing.

"Let everyone know that Lobelia is awake,"

"Certainly," Baldric said before looking at Lobelia. "Baldic is happy to see you better, Master Lobelia,"

He then disappeared in another puff of smoke.

"I will be right back," Monarda said before leaving.

Lobelia put down her glass onto the side table and sank into her bed,groaning, Her mind was whirling. Magic? House elves? Somehow, she ended up in the Harry Potter universe.

A week passed before Lobelia was allowed to leave her bed. During her time bedridden, she mostly thinked; her memories eventually sorted themselves out.

She was no longer Lavender Pence, an orphan high schooler from Florida, but Lobelia Prince, a pureblood witch about to embark in her fifth year into Hogwarts.

There was little Lobelia missed about her previous life. Shuttled from foster family to foster family since she was a baby, there was no one she would miss from that pitiful life. The only saving grace was that she was a fan of Harry Potter and watched all the movies. Now that she thought about it, it wasn't much of a saving grace. Somehow, she had reincarnated into the year 1976 which made no sense. How could she go back in time from 2024 to 1976? She couldn't think of any other way for it to be possible other than magic. Not that her foreknowledge of the future held anything useful for her time. Of course, that wouldn't stop her from making a change. Too many people had died in the book. Maybe, she could prevent some casualties.

Lobelia repeatedly had nightmares of her death as Lavender Pence. She was on her way home from school, walking since she missed the bus again. School wasn't that far from her current foster home, about a 30 minute walk. The walk was uneventful until she crossed the street to her house. All she heard was the blaring horn of the oncoming truck before everything went painfully black. And she would wake up in cold sweat. Lobelia doubted anyone would miss her in her old life.

"Lobelia, dear,"

Lobelia blinked out of her stupor and turned around. She was staring out the hallway window at the flower garden when she was interrupted by her mother.

Gypsophila Prince exuded elegance from the way she walked to her fine burgundy robes. They couldn't have been more different. While Lobelia was short and slender, Gypsophila was tall and plump. Her mother had bright curly chestnut hair in an elaborate braided bun, adorned with jewels. Lobelia's black hair was pinned into a simple half-up do using her favorite silver hairpin. The only similarities that they had were their grey eyes and beauty mark above their lips.

"You have received mail," Gypsophila said, handing Lobelia the parchment. "It's from your fiance,"

Lobelia's stomach curtled like sour milk as she took the parchment.

Walden Macnair. He was one of the named Death Eaters in the Harry Potter movies. She remembered shuttering whenever she saw him on screen. He was the executioner that was supposed to execute the Hippogriff, Buckbeak, in the Prisoner of Azkaban movie. She wanted nothing to do with Macnair even before she gained her past life memories. In their first meeting, she knew straight away that he was a bloodthirsty, terrible man.

"What does it say?" Gypsophila asked, hovering too close for comfort.

Lobelia pursed her lips.

"Before I open this, there is something I have been meaning to ask you,"

"What is it, dearie?"

Lobelia stood there quietly for a bit, her heart pounding in her ears. Before she got her previous memories, she would have never had the courage to make such a request.

"Well…I want to break my engagement with Macnair," she said.

Gypsophila's smile contorted into a deep frown and her face turned red with rage. But she was not one to shout. No, her anger was as quiet as a predator pursuing prey. She gripped Lobelia's arm, causing her to yelp. Her mother's grip was so tight that Lobelia knew it would leave a bruise. Her sharp manicured nails sunk into her skin.

"How dare you ask me that. It is your duty as a woman to be married once you come of age. This arrangement has been made since you were an infant," Gypsophila said through gritted teeth.

She gave Lobelia a harsh shake.

"Can't you see how lucky you are? You are not going to be married off to some unknown family like some bargaining chip like I was. You are going to marry Ethel's son. May she rest in peace. She was a good woman who had done so much for this family. Do you want to tarnish her good name with your puerile wants?"

Lobelia shook her head, blinking away welled up tears.

"No, Mother,"

Gypsophila released her vice grip and began rubbing her temple.

"Great, now I'm the bad guy,"

Lobelia couldn't meet her mother's eyes as she rubbed her throbbing arm. She should have known that it was going to end up like this.

"How about we go shopping and forget all about this," Gypsophila said.

Lobelia shook her head. She just knew that her mother wasn't going to let her pick anything out for herself and just play dress up with her.

"I'm still feeling a bit weak. How about some other time,"

Gypsophila gave her a placid smile and caressed her cheek.

"Okay, dearie. You know I love you. I'm only doing what's best for you,"

Lobelia only nodded, a lump forming in her throat. She waved a small goodbye to her mother before leaving.

She walked down the empty hallway and turned into the library. The room always gave Lobelia a sense of wonder, its walls massive and filled with hundreds of isles of books. It was almost as big as the one at Hogwarts. Lobelia situated herself on a sofa by the fireplace, staring at the parchment. With a sneer, she chucked it into the fire like yesterday's trash.

Watching it burn, it gave her no satisfaction. Nothing has changed. Does she have the power to change anything about her life? How could she save anyone when she could not even save herself?

Lobelia looked around the room, taking in its brilliance when she stopped at a huge tapestry. On it, it was the Prince Family Tree, its large branches expansive on the top before becoming narrower on the bottom. Standing before it was her father, Cedrus Prince.

"Father?"

Cedrus turned around and gave Lobelia a small smile, beckoning her over.

Lobelia could tell she got her looks from her father. He was tall and gaunt, looking uncomfortable in his expensive robes. His short black hair was combed into a classic quiff. There were bags under his russet eyes, reflecting years of trouble that had never quite been solved.

Cedrus gave Lobelia a side hug, immediately sensing that something was wrong.

"What's the matter, little snake?"

Lobelia tightened their hug.

"I am just…worried about my engagement to Macnair. Is there any way for it to be broken?"

"Did you ask your mother about this?"

"Yes,"

"And what did she say about the matter?"

"No,"

"Then my hands are tied. Your mother is in charge of your engagement and also your little brother's,"

Lobelia shifted her feet.

"But Penstemon likes his fiance. You see how much fun they have during their playdates. Macnair is different. He's terrible, dangerous even,"

"And what makes Macnair so dangerous?"

That made Lobelia pause. Other than her foreknowledge of Macnair in the movies, he never actually did anything that could reveal his evilness. It frustrated her to no end.

"I know that you are nervous about your engagement, but everything will be fine. You know, I was also extremely worried about my marriage before I met your mother. But, everything fell into place once we got married. You know, despite popular belief, love is learned. Eventually, you will learn to love Macnair,"

Lobelia wrinkled her nose at the prospect. That was never going to happen. Knowing that talking about her horrid engagement was going nowhere, she looked at the elaborate tapestry of the family tree.

"We have a lot of family members,"

"Had a lot of family members," her father offhandedly corrected, gazing at the family tree, "So few of us are left,"

Lobelia furrowed her brow. She noticed that there was a hole in the hanging, looking as if it was burned through. When she looked closely, she could see parts of a name.

"Who is the person next to your picture?"

Cedrus gently ran his hand over the hole. Lobelia could tell that he was having internal conflict.

"That is…my older sister. Your aunt Eileen,"Cedrus said, teary eyed.

"What happened to her?"

"She was disowned by the family. Your Grandfather Severus was furious with her when she fell in love with a muggle. He never saw her again after that. I miss her everyday,"

Lobelia felt the cogs in her ming turning, connecting the dots. Her grandfather was named Severus, did that mean—

"What was the muggle's name?"

Cedrus looked deep in thought,

"I believe his name was Tobias Snape,"

That blew Lobelia's mind. She couldn't believe it. She was related to Severus Snape. It was all there. He was the Half-Blood Prince after all. Why didn't she realize this sooner.

"Can't you contact Aunt Eileen? You are the new Head of the House. You can bring her back into the family, right?"

Cedrus' eyes shined a glimmer of hope, but it died as quickly as it came.

"It's been so long, too long. I shouldn't disturbed her," he said, shoulders slumped.

Before Lobelia could argue, someone bursted into the library.

"Father!" a little boy cried.

It could only be was a charming boy with chubby cheeks. Her little brother recently turned 6. Lobelia doubted it was that fun of a birthday since she was at death's door suffering from Dragon Pox when it happened.

"Have you seen Alfie? We were playing hide-and seek and now he's gone!" Penstemon cried, tears flowing from his heterochromia eyes.

"Don't worry, I'm sure your toad is somewhere in this house," Cedrus said, wiping away Penstemon's tears.

"But I looked everywhere. No Alfie,"

"Have you checked under your bed, Pen?" Lobelia asked. "He was there the last time you lost him,"

Penstemon shook his head.

"That was the first place I looked. I checked my room, the dining room, even the kitchen! And nothing," he said.

"Please help!"

Penstemon began to weep harder.

"What if he's hurt,"

"I am sure he is fine," Cedrus said, picking Penstemon up.

"Yeah, don't worry," Lobelia said. "Let's get to searching,"

And they were on the prowl. Eventually, Alfie was found. The sneaky little toad was under Lobelia's bed.