Sunday morning, John awoke in the Hospital Wing to find Sherlock had disappeared. Sitting up, he saw that poor Julia Stoner was still lying motionless in her bed, looking quite blue. He sighed sadly, got up and walked down to breakfast. On his way, he met Sherlock in the Entrance Hall.
"Have you seen the notice boards, John?" he asked
"No, I haven't been up to Gryffindor Tower yet. Why, what's happened?"
"Well," Sherlock bounced on the balls of his feet, "I know how you just love Potions - and you're very good at it, by the way - I was just wondering whether you were interested in joining Potions Club with me? There's a meeting for new members at ten"
John laughed, "Okay, I'm interested"
They arrived at Greenhouse One at the appointed time. Professor Trevor and a few seventh years talked about Potions Club: what you did and the advantages of joining it and all that jazz, and soon everyone present became official members.
John turned to Sherlock as they re-entered the castle,
"You only wanted to join because of the attack on Julia Stoner,"
"Of course"
"Do you really think it was an attack?"
"How could it be an accident? Professor Trevor makes a good point in asking why someone would drink from an unlabeled potions bottle, especially when the older students dabble with experimental poisons"
"What if someone accidentally poisoned her?"
"If it was an accident, why did they run away?"
John nodded,
"So, who do you think it is?"
"It's got to be someone she knew otherwise she wouldn't have engaged with them long enough to poison her"
"Right, but, that could be anyone!"
"John, the incident occurred at a quarter past nine-"
"I was out that long?"
"-and the only people who would have been around are the Potion Club members, fourth years and up. That narrows our range of suspects dramatically. Also, Moonseed poison, would only be found in Greenhouse Three, and Professor Trevor would have noticed if someone strange was hanging around"
"What about Trevor's office? Wouldn't Moonseed poison be there?"
"Moonseed is a plant and a very poisonous one at that, so we can safely assume it was taken from one of the greenhouses, Greenhouse Three being more likely"
"What if it was Trevor who poisoned Stoner? We only have one witness, and that's Professor Trevor himself!"
"Why would Professor Trevor poison one of his best students? I don't see any logic in that"
"Who did it then?"
"Well, we're going to have to form a list of suspects"
"So, a list of all the Potions Club members, years four and up?"
"Exactly!"
. . .
Monday, after lessons, John and Sherlock headed into Greenhouse One for Potions Club. There were several students talking animatedly with each other while creating bright coloured concoctions in their cauldrons.
"Ah, hello boys!" someone cried
Professor Trevor rushed forward and shook John and Sherlock's hands enthusiastically
![The Case of the Meddling Siblings [BBC Sherlock - Johnlock] by destinationtoast](https://img.wattpad.com/cover/108266351-80-k936681.jpg)
"Sorry if I don't remember your names"
"I'm Sherlock Holmes, and this is John Watson," said Sherlock gesturing to himself and John
"Ah, that's right. Well, welcome to Potions Club! At the moment we're just warming up and brewing some simple potions. Why don't you go and get to know the others?"
"I think we will, Professor"
Sherlock scanned the many happy faces before heading to an empty cauldron set up near a couple of Ravenclaw girls. John followed, taking the cauldron next to his. When he looked up at the girl opposite him, John nearly jumped out of his skin. It was Julia Stoner! But, on closer inspection, John realised the girl merely resembled her.
She smiled at them,
"Hello! Are you new members?" she asked
Sherlock returned the smile,
"Yes, we are. I'm Sherlock Holmes" and he offered his hand
The girl took it,
"Hello, Sherlock, I'm Helen Stoner. And you are?"
"John Watson" John replied, shaking her hand too
"Hello, John"
Sherlock peered at Helen,
"Have I seen you before? You look familiar"
John opened his mouth to say she was obviously a relative of Julia Stoner but Sherlock stood on his foot, causing John to fall to the floor with a grunt of pain.
Helen laughed,
"Well, I don't recognise you, but I do have a twin sister"
"Oh!" Sherlock cried, his face lighting up with realisation, "A twin sister? What's her name?"
"Julia"
Sherlock snapped his fingers,
"Julia, that's right. I thought she did Potions Club, where is she?"
Helen's smile faltered,
"Er…she's in the Hospital Wing. She was poisoned"
"Most unfortunate," a voice drawled
A tall boy with slick brown hair and narrow, dull eyes siddled over. A small smile played across his thin lips.
Helen grimaced,
"Go away, Armitage!"
The Slytherin boy held out his hand to John and Sherlock,
"Percy Armitage. It's good to see such youngsters joining up. And such a pity poor Julia isn't here. Now she'll have no chance of winning the Best Potioneer of the Year Award"
He smirked.
"Best Potioneer of the Year Award?" John asked
"One of the trophies given out at the end of the year," Armitage explained, "and the most sought after"
"Yes," said Helen, "and Julia is the best candidate this year"
"Arguably" Armitage interjected
"I take it there is some competition between you and Julia" said Sherlock
"Oh, yes," Armitage replied, "ever since we first joined Potions Club"
"You knew her beforehand, then?"
"No, I'm in the year above. I'd never seen her before the first meeting"
"Are we talking about Julia Stoner?"
