Fred and George Weasley had just pulled an all-nighter. That wasn't so unusual, but the reason that they had done it was. Professor Dumbledore had announced at the welcome feast the previous night that Hogwarts would be hosting the Triwizard Tournament this year. The Tournament was a once in a lifetime opportunity; it was a world-renowned competition between the three best magic schools in the world; Hogwarts School of Witchcraft and Wizardry, Beauxbatons Academy of Magic, and Durmstrang Institute. The tournament had been held every five years until it had been banned after an incident involving a Cockatrice escaping and injuring the three judges at the 1792 competition. Students had been known to die while taking part in the three tasks of the tournament.
The winner of the Tournament would receive eternal glory but that's not what interested the twins, they were interested in the ten thousand Galleon prize fund. Ever since Ludo Bagman had conned them out of their winnings at The Quidditch World Cup, the twins had seen their dreams vanish before their eyes. They saw the Tournament as the only way to reclaim their dream of owning their very own joke shop.
The only problem the twins faced when entering the tournament was their age, Professor Dumbledore had informed everyone at the welcome feast that the only people who could take part were sixth and seventh years who were of age in the wizarding world. Fred and George were not of age. At the age of 16, they had seven months until their birthday on April 1st. Due to this discovery, the twins had slipped away from the party they threw in the common room each year to the secret lair that they had created.
The lair as they called it was hidden behind a tapestry of the Hogwarts crest on the fourth floor of Hogwarts. They had discovered it at the start of their second year after seeing a house elf walk through it. Upon following the elf, they had found tunnels that weren't on the Marauders Map, one of which led to a large room that looked to be an abandoned classroom caked in decades of dust and grime. They had later gone to the Kitchen to ask the elves what the tunnels were. They were informed by the elves that centuries ago the passages led to teacher accommodations and where married couples who still attended school lived. They were also told that the rooms and tunnels were hardly used anymore.
Over the years the twins had created a lab within the room and had added their personal touch to the space. They were able to design, create and mass produce their products without getting caught. Each wall within the room was painted a different vibrant colour like orange or green, and within the room, they had shelves of ingredients, books, and products of their own creation. In one corner they had bean bags, sweets, and games so that they could relax when they waited for the next steps of their potions.
The twins had gone to their lair after leaving the Gryffindor Common Room; only instead of creating their products as they so often did, they had gone there to brew an aging potion, it was simple to brew with their skills, as the twins were quite skilled when it came to the subject taught by their least favourite teacher, but it was also incredibly time-consuming. The potion had needed to be watched constantly throughout the night and had repetitive steps that grew tiresome after hours of repeating them. At one point the potion needed to be stirred five times clockwise followed by two times, counter clockwise for an three hours, this had theft the twins with little time for reprieve throughout the night as they took turns; one twin preparing the ingredients while the other was overseeing the cauldron.
The potion had taken ten hours to brew, but for Fred and George, it was worth it if they got the opportunity to enter the tournament and win the money needed to set up Weasley's Wizard Wheezes officially; they had a dream of a vibrant store, in the centre of Diagon Alley; with whirling gizmos and pranks better than anything Zonko's could dream of. George had carefully ladled the contents of their caldron into two small glass Phials, handing one to his twin. After waving his wand to clear up their workstation the pair had grabbed their bags, prepared the night before after summoning their timetables from McGonagall's office and both twins left their lair, Fred taking the lead as they headed down the winding passageway to the tapestry concealed entrance on the fourth floor.
Upon reaching the tapestry, Fred stepped out quickly closely followed by George neither of them bothering to check that the coast was clear. As he stepped out, George watched his twin crash into what appeared to be poorly dressed, out of sorts Hermione Granger. He watched in slow motion as his twin fell forward onto their young friend who seemed to grab at him as he fell upon her, Fred's right knee firmly on Hermione's stomach, the petite witch gasping in pain. Somewhere in the background of his mind, he heard the distinctive sound of smashing the glass bottle smashing and his twins whisper of Hermione's before a bright light like that of Magnesium within a fire surrounded the two.
When the light faded, George could not comprehend what he was seeing, where his twin and Hermione had been were two children, unconscious and in clothes too big for their tiny bodies. When asked later how long he stood, his mouth open like a fish out of water George would not be able to answer, he stood parallelised in shock until he heard hurried approaching footsteps. When he looked around, he found the headmaster approaching at a steady speed an unsure look upon his old, bearded features.
A short time later George found himself sat in the hospital wing waiting for his twin and Hermione to wake up. Upon finding them, Dumbledore had levitated the two there at a distance so that the substance on their skin couldn't transform him or anyone else into children. When they had arrived, Madam Pomfrey had performed a necessary diagnostic charm upon them and had also cleaned up and changed the two into clothing that fit their tiny bodies. The diagnostic charm had shown that the two were perfectly healthy for their current age other than the cuts caused by the broken glass. The cuts had been quickly healed with a flick of Madam Pomfrey's wand and she had told George to stay with them until the pair regained consciousness.
Madam Pomfrey had told him that at Fred and Hermione's current size it would be dangerous to perform too many spells on them, so he was left waiting for them to wake naturally rather than using Rennervate spell to wake them up instantly. She had also told him that they couldn't use potions on the pair as it could react badly with the ingredients currently in their bodies. This meant that they were stuck waiting for the two to come round on their own accord. When they did so, they would learn whether they held their current memories or that of their younger self's.
George waited patiently between the two for three hours before movement occurred. On both sides, the children wriggled about and slowly sat up, both with mischievous smiles on their little faces. Fred was the first to speak, telling him he looked like a Weasley, but he couldn't be because he knew all his family. He had then wondered aloud where George was causing the smile to slip away from George's face. George had then turned to Hermione hopeful that his twin was pulling a joke. Upon looking at her shocked gaze and following her line of sight to a mop cleaning the floor on its own accord, he knew that Fred wasn't joking around; Fred Weasley and Hermione Granger had become children and had no knowledge of life past the current age of their tiny bodies.