First take one ghoul. Stun it, and stuff it into pyjamas before it has time to struggle. Add red hair. Cover the final product liberally in large painful boils. What you produce using this method should be a perfect replica for a Weasley with spattergroit - and if Fred and George were right, better looking than Ron - and the rest was straightforward.
"It can't still be at it?" Arthur said despairingly, "It's three in the bloody morning."
Molly stared at the ceiling with intense concentration. It was the sort of thing you did when your youngest son was off trying to be an outlaw, and every time you managed to forget that for almost long enough to start nodding off to sleep a ghoul banged against the wall.
Amazing what you noticed when you stared at it for long enough. Cracks, cobwebs and evidence that someone's mind hadn't been on the painting charms. If she had to be awake for much longer, she was going to tell Arthur it needed a fresh coat of paint.
"I thought you said you and the twins soundproofed the room?"
"We did! It's loud enough to get through the Charms."
There was a crash. Molly winced, and tried not to imagine what might have been broken, "I'm sure it's never been this loud when it was in the attic."
"Moving it downstairs seemed to get it a bit worked up. It should tire itself out and calm down soon," Arthur answered, trying not to think about just how few hours were left before he had to get up for work the next morning, "I hope."
"Mum? Dad?" There was a knock on the bedroom door. Most of the Weasley children learned fairly early in life not to charge into their parents' room without knocking unless they wanted to be potentially traumatised for life. Bill had assured his younger siblings that they would instantly be struck blind if they saw such things. Fred and George in their own inimitable fashion had decided to use this piece of family lore as a marketing angle for the adult markets of their Peruvian instant darkness dust.
Conveniently that strategy, or the existence of the lucrative adult market never got mentioned over the dinner table. Molly would never have known if she hadn't been... well, with seven children, you had to have some interest in things outside cooking and cleaning.
"And now it's waking the children," Molly said with a sigh, "Come in!"
The door opened, and the twins trooped in, one after the other, both fully-dressed.
"We can't sleep," Fred? – no, George, Molly corrected herself immediately noting the missing ear, and then feeling bad about it. What a way to recognise your children.
"That ghoul's making more noise than Bill does when he has Fleur over."
"We're going to sleep at the shop."
"Now, boys, don't be hasty," Molly said quickly, sitting up, not liking the thought of the twins being out there alone. Or more to the point, her and Arthur being alone here. "I'm sure it'll quiet down soon."
"I wouldn't be so sure of that," Arthur said, not missing how quickly his wife had stopped complaining of the ghoul's noise when her sons complained of the same thing. He thought again of how soon morning would arrive, and how long a work day would feel on that small amount of sleep. "Maybe we should all go sleep at the shop."
The two boys glanced at each other, and shrugged.
"At least the noisiest thing we've got there is the pygmy puffs. They just hum a bit sometimes."
"Yeah, nothing like this."
"This isn't going to work," Molly protested as Arthur climbed out of bed, "By the time we've all got dressed and got to the shop, it'll nearly be time to get up anyway. And how are we going to explain sleeping at the shop to anyone investigating Ron's illness?"
Arthur paused to consider this, "Really strict quarantine?"
"And the way it keeps charging about like that?"
"Delirium due to fever?" he suggested hopefully. He rubbed his eyes, "Look we've got to do something or none of us is getting any sleep tonight."
A loud thump from Ron's room only served to underline that point.
"Look, couldn't we just put it back in the attic, and work out what to do with it in the morning?" Molly said helplessly, "It seemed happy in the attic."
"Not unless you want to try and get it back into those pyjamas." Fred said firmly.
Arthur gave more thought to the idea, "Maybe we could just let it keep the pyjamas on?"
"Can't," George shook his head, "Dust. They'll be filthy by morning."
"We'll use Evanesco," his father suggested desperately.
"The rate we're going, if we don't get some sleep, we'll vanish the ghoul not the dust." Tiredness was putting a dint in Fred's usual good humour.
"Let's just go take a look at it, before we do anything silly like rushing off in the middle of the night, shall we?" Molly said firmly, "It's not safe out there at this time, especially not at present. Someone's bound to wonder why people are flying about in the early hours. There's bound to be something else we can do."
No-one seemed to have any objections to that idea at least, and once both parents had located their slippers and dressing gowns all four of them headed to Ron's room to see if they could think of anything.
The ghoul seemed to be in the most dreadful state in there. It rushed about frantically, its usual moans almost at a scream, stripy pyjamas flapping wildly. Belongings and furniture lay scattered about the room where they had been pushed or thrown.
"Oh dear," Molly viewed the scene with a sigh, "That's going to take a while to clean up. And it was so tidy when Ron left."
"More to the point, no-one is ever going to believe that's Ron," Arthur said, frowning as he watched the ghoul.
At his side, George snickered, "Oh, I don't know about that. That looks just like Ron's room in its usual state to me. Adds realism."
The ghoul hurled itself at a wall with a loud wail. It seemed to be the final straw for Fred who gave the door a kick, at his limits of patience, "Shut up, shut up, you bloody stupid thing! Just put a bloody sock in it!"
"George!" Molly said reprovingly.
"What? I didn't do anything!"
"Sorry, George. Fred! Mind your temper!"
"Sorry," Fred subsided, a little sheepishly, "Just we're meant to be opening the shop at eight."
"Never mind that," Arthur was watching the ghoul inside the room, tone holding a hint of excitement suddenly, "Fred, kick the door again."
Fred blinked at his father, "What?"
"Kick it again! Go on."
"Arthur, I don't think he needs to start damaging the doors just because he's tired…" Molly started to protest, fearing how long they would last under the temper of a teenage boy. Fred, however, had already done as he had been told, lifting his foot to give the door a good kick.
Inside the room, the ghoul had paused, head tipped to one side as it looked towards the door.
"It's working!" Arthur grinned with triumph and relief, "Do it again, Fred."
"Now, wait a minute," Molly interceded hastily, "If he carries on like that, you'll end up kicking the door down, and that won't help anything."
"No," Molly said firmly, "You've got a wand. Use that."
It was a thought that clearly hadn't occurred to any of the others up to that point, and Arthur looked a little disappointed when he realised he'd left his own wand in the bedroom. The twins meanwhile produced a fine chorus of magical bangs and clatters.
The ghoul listened, and then sat down on the floor suddenly, quietly down. It rapped a fist against the floor, a far softer and more questioning sound than any it had produced previously.
"Ah, look." Despite her tiredness, Molly softened. "It's trying to communicate."
"I thought so," Arthur said smugly, proud of his discovery, "It's used to the cistern, you see? Banging back all the time. Without the cistern…"
"It was lonely," Molly completed the thought, "Oh, the poor little thing. No wonder it was making so much noise. It must have been hoping the cistern might hear it."
Out of sight, behind her back, Fred and George glanced at each other and rolled their eyes.
"Better make sure Ginny doesn't find out about that," George murmured under his breath, "You know how soft she gets. She finds out it was lonely and she'll be dragging it to school with Arnold."
Fred brightened at the idea, "You know, there might just be a product idea in that," he commented, "If they were smaller… and cuter."
"Ghouls in pyjamas?" George considered it and nodded, "We could make the banging a plus point – like "how to tell if you're not paying your ghoul enough attention" What were the name of those Muggle toys from the catalogue we were looking at for ideas? Tamagotchi? We could do that! Grow - "
" -Your own ghoul from mold. Dress in pyjama's and-"
"-make sure it gets enough sleep and knocks with-"
"-different knocks for different things and-"
"I'm sure you boys can work your ideas out in the morning," Arthur said, "In the meantime, unless you both want to leave your wands outside Ron's door all night, let's see if we can get something rigged up to keep it quiet, shall we?"
"Right," Fred looked again at the ghoul, and considered for a moment. "How about an extendable ear? We could set one up so that it led from the cistern down here."
"We could hide the end so that anyone visiting wouldn't see it." George agreed.
"I've got one in my room."
"It'd only take a minute to get it put into place."
Apparently happy now they had a solution to the problem the pair set off to fetch the ear and get it put into place. Their parents decided wisely that perhaps now was not the best time to ask why Fred was keeping an extendable ear around the house.
The ear did indeed seem to be just the thing. Once its familiar noises were filtering into the room the ghoul's usual moans turned into something almost resembling coos. Going into the room, Molly took its arm gently and even managed to coax it into getting into bed.
"Poor little thing," she said again, softly this time as she tucked it in, "All that fuss because it couldn't hear the cistern any more. I wonder if it thinks it's another ghoul?"
"It's a ghoul, Molly," Arthur warned from the door, "I doubt it really thinks anything. Don't go getting too attached. It isn't really Ron."
"I know, I know. I just…" she didn't finish that thought because it would've meant twisting her anxiety further and further, but instead gave the ghoul a quick pat on the shoulder as she stood, heading back towards the door, "Do you think they're all right?"
The question seemed to come from nowhere, but Arthur didn't need to ask who she was referring to. He slid a comforting arm around his wife's waist. "I'm sure they're fine," he reassured as best he could, "They're sensible kids. They'll do okay." He kissed her lightly, a quick gentle gesture of affection, "Come on. Let's go back to bed."
It was four in the morning when they finally settled back into bed, and Arthur reflected glumly that he might at least get three hours of sleep before he had to get back up for work.
"Yes, dear?" He shifted to face Molly, expecting perhaps a question about the ghoul or something about Ron and the others.
Instead she yawned, and moved to snuggle more closely into his side, "Remind me in the morning. The ceiling needs painting."