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Genetic Drift

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Someone knocking at Danny Fenton’s window in the middle of the night was hardly ever a good thing. In fact, as Danny rolled out of bed at 2 am to investigate the source of the knocking, grumpy after being woken up from much-needed sleep, he decided someone (or, more often than not, something) knocking at his window in the middle of the night was never a good thing.

You could’ve gone to Florida or something, but nooo you just had to return to Amity for spring break, he grumbled, shuffling over to his window. It wasn’t like this never happened at school- it did. It just happened a lot less than it did in his hometown. With a sigh, he opened his window and stuck his head out to look around.

No one. There was no one there. Groaning he turned to go back to bed.

“Hey, cous’.”

Startled, Danny whipped around to find nothing other than a little girl (who really wasn’t much of a little girl anymore) with her head and arms propped up on the window ledge. He recognized her instantly.

“Dani? Wha-what?”

“Can I come in?” She asked, already making her way through the window.

“Um, what?” Danny stammered in reply.

With a thud, the girl climbed through the window and sat down on the floor. Almost immediately there was a flash of blue-white light and a different looking girl sat in her place.

“I- don’t…but…you…okay?” Danny asked, rushing over to her side, hardly able to form words.

Dani brushed him off with a wave, saying “Yeah. Great. Just need a second,” before closing her eyes and controlling her breath like someone in a yoga class.

Danny stared in disbelief at his younger cousin as she caught her breath. He could hardly believe she in front of him if he was being honest. The last time he’d seen her had been, what, 7 years ago? He had been 14 then, and he was 21 now which made her…18? Okay, that was weird. Her black hair had grown out and hung down near the middle of her back and her face was more angular, giving her a generally older look. But she also looked tired. There were dark circles under her eyes and the back of her hands were scratched and bruised, like she had spent her spare time punching sand.

“You guys got any water?”


“Hello? Earth to Danny, you copy?”

Suddenly, Danny snapped as he processed what exactly had just happened. With an alarmed look on his face and his eyes ever so briefly flashing a bright green colour, he spoke. “Danielle. Downstairs, lab, NOW.”

Groaning with the effort, Dani stood up and faced her cousin, his hand pointing out the door to his room. “Geez, so much for a warm welcome,” she mumbled, limping past Danny. A moment later he followed her and the pair made the trek to the lab.

Danny didn’t speak a word as they walked down the stairs. There was so much swirling around in his head he feared any attempt to speak would cause it to all come out at once, very loudly. He knew something had to be wrong, really wrong, for Dani to show up like this. The last time she had shown up unexpectedly it was because she was dying- literally breaking down on a genetic level. After Danny had been able to stabilize her she flew off to her next great adventure, and he hadn’t heard from his clone since. Until 3 minutes ago, that is. Which most certainly meant something major was wrong. He could tell from the way she moved that she was hurt. Before she had transformed there were cuts and bruises on her arms and a nasty looking gash on her cheek the oozed green ectoplasm. When she had changed back they faded, but the cuts were still there, tinted a sickly green.

“Hold up,” She said, stopping suddenly, “Give me like, 20 seconds, kay?” Slowly, she sank to the floor, sitting on the bottom step of the main staircase. Taking very controlled yet somehow still ragged breaths, she placed her head between her knees, fighting the nearly overwhelming sense of vertigo that she had felt for the past few weeks. You really fucked up this time, a small voice told her.

“Danielle? Dani? You alright there?” Danny asked.

Dani lifted her head to reply, looked up at her cousin, and fainted.


Great. This is just great, super awesome, Danny thought as he made his way towards the basement stairs. Dani was in his arms, still breathing but almost completely out. He should have figured something like this would happen sooner or later given the insanity that was his life. But he wasn’t ready for something like, or the mixed emotions he was currently feeling because of it. As he reached the bottom of the stairs he looked for somewhere to place his cousin and decided on his Dad’s old overstuffed office chair. Gently he set her down and went to find the first aid kit.


Dani woke up a few minutes later. Her surroundings were unfamiliar and standing above her was a boy with dark hair and blue eyes placing a cold compress on her forehead. Her cousin.

“There she is. You okay, Dani? Everything is safe, you just fainted. You’re in the Fenton lab. I’m going to figure out what’s going on, okay? But first you are going to be really sleepy for bit.”

Only somewhat processing what he cousin said, Dani nodded her head and fell asleep.

The next stretch of time was a blur for Dani. What she occasionally saw and heard meant nothing to her, so she slept again.


After giving Danielle the anesthetic, Danny picked her up and moved her again to one of the lab’s hospital beds. He never knew why exactly his family had them, but he was certainly grateful for them tonight.

His cousin’s condition worried him. A lot of things about his cousin worried him at the moment, but right now her stability took priority. It really was just like Plasmius to go and create a sentient clone without giving them the key component to their existence. It made him sick, yet he was not surprised.

It hadn’t taken him long to figure out Dani’s immediate problem. Her genetic code had gone unstable again. That much was obvious. After setting her down in the chair he had been covered in some kind of weird ectoplasm. She was literally dripping the stuff, melting down to it. It had happened before, but the two other times he’d seen it, it had been right after she used her powers. Now, she was just melting down as she sat there. It was bad. Really bad. To get better she needed a genetic sample from him, a working and complete genetic sample. They may have been clones, but they weren’t the same. As hard as he tried, Danny just couldn’t figure out why Danielle’s DNA had the stability issue. Clearly, his DNA wasn’t affected by his transformation or using his powers. There was just a flaw somewhere inside Dani’s code was really all he could guess.

After lying her down he collected everything he needed to make a stabilizer. She was injured and dehydrated too, and even though he didn’t want to put her under anesthetics, it was the only thing he could think of (short of an induced coma, which he had no idea how to do) to slow her destabilization. So a mix of his genetic code and some electrolytes was all it was going to be for now. The electrolyte mixes his parents had on hand. The genetic sample he had to collect himself. 

The DNA she needed was from the moment between when he was human and when he was a ghost. The normally split second in time where his appearance and abilities were altering, the moment when the infected ghost DNA took over from his living DNA, was what Dani needed. The best way to get that he’d learned was a blood draw. Or ectoplasm draw? Whatever it was (and he wasn’t entirely sure he wanted to find out), he needed it.

Taking a deep breath, Danny picked up the syringe from the table in front of him. Yeah, he’d fixed himself, his friends, and even Jasmin up after more than a few ghostly mishaps, but taking blood was different. The syringe was huge, and the needle was too.

Trying hard to not think about what he was about to do, Danny took the needle and stabbed it into his forearm, wincing from the pain. He took one more breath and transformed.

It was, by all accounts, a slow transformation, with his focus divided between going ghost, pulling the plug on the syringe, and not yelling from the pain. But it was over soon enough, and there stood Danny Phantom, ghost-boy, superhero, and over-stressed college student, with a large, glowing, green liquid filled, syringe sticking out of his arm. Clenching his teeth, he pulled the syringe free and set it on the table. He was going to have one hell of a bruise to explain.

After mixing the stabilizing solution together he poured it into a drip bag and hooked Danielle up to the IV. About an hour had passed, he realized, and she should be waking up within a half hour. Knowing he’d done all he could for the time being, Danny pulled up a chair and sat down. It was 2:00 am.