Disclaimer: All but the plot is JK's.
"Tartangella!" Remus Lupin yelled, smirking as he watched James Potter suffer from the spell. He ducked quickly as James retaliated, narrowly missing a mild stinging hex which hit Peter Pettigrew in the nose. Peter grabbed his own wand and shot a badly pronounced body bind at James, James dropped to the floor and watched as the beam of light flew past him and hit their roommate Sirius Black square in the face, the light engulfed Sirius and none of them could see the black haired teen, When the light finally faded Sirius was no longer there, In his place was a toddler. "Shit!" The toddler stared at them all for a while, cocking his head to one side.
"Peta!" He suddenly said, "What choo done?! Emus! I'm 'ittle!!!" They all stood there, stunned, for a moment, Remus was the first to recover, he walked over to Sirius,
"We'll go to Dumbledore, he'll know what to do. Can you walk?" Sirius nodded and tried to stand but ended up flat on his bum, he scowled, daring anyone to laugh. "Do you mind if I carry you?" Remus asked softly, Sirius shook his head but Remus could see his bottom lip wobbling. Remus picked Sirius up before going under the invisibility cloak so nobody saw them, The second they were under the cloak a tear fell from Sirius' eyes, damn toddler emotions! Remus wiped the tear away and stroked Sirius' hair as his de-aged friend buried his head in Remus' shirt. What the hell were they going to do?!
"You have, it seems, de-aged Mr Black." Dumbledore said sternly, watching the three teenagers squirm, Sirius let out a chuckle from where he was perched on the headmaster's knee. "Mr Pettigrew, as you are behind with your school work you will be punished with a months worth of detentions. Mr Potter, Mr Lupin... I have something a little different for you as you are both top of your classes. I want you to look after Mr Black here." They gaped at him, "Poppy will be on hand to offer advice and your teachers can send you your work."
"Sir, I can't look after a toddler!" James burst out.
"Not an 'oddler!" Sirius scowled.
"Well tehcnically you are so you might need assistance with some things." Remus smiled.
"Wait, what? Moony you can't seriously be going along with this?!" James snapped.
"Mr Potter let me put it this way, either you help Mr Black here or you shall find yourself in detention for a very long time." Dumbledore said calmly.
"You're blackmailing me?!" James asked stunned.
"You could say that."
"Fine." James snapped and slouched down in his seat.
"Not an 'Oddler!" Sirius decided to yell again, Dumbledore simply smiled and left the room to make arrangements, taking Peter back to his classes, and on the way out he set Sirius on the desk. "Not an 'Oddler!" The toddler repeated.
"Sirius, you have your memories from now but mostly mentally you are a toddler, and you are physically a child as well." Remus explained patiently, feeling bad for his friend.
"NOT AN 'ODDLER!" Sirius screamed.
"Sirius Orion Black don't you raise your voice with us!" James snapped and wondered if he'd gone too far as Sirius pouted and buried his head in his hands but Remus was giving him an approving look.
"Well he's toilet trained which is a help... It wont be so bad Jay..." Remus whispered.
Sirius peeked through his fingers, "You ang'y 'Ames?" He asked, they could hear the fear of regection in his voice.
"Yes I'm a little angry at you, you know it's wrong to yell. However I will forgive you, If you shout at Remus or I again the consequences will be severe though." James promised, standing up and walking to the desk, picking Sirius up as Dumbledore walked back in. Sirius didn't reply, he did bury his head in James' shoulder though. "Well I have a holiday cottage in north Wales that you can use, Poppy is going to do a quick check on Mr Black so why don't you go and pack your things?" Dumbledore asked as Poppy Pomfrey the medi-witch walked in. Numbly Remus and James stood and left, James placing Sirius back on the desk as he went.
When they got back to the office Dumbledore told them that Sirius was currently four years and two months old, he appeared fine apart from a couple of scars on his back which they may want to ask the boy about, they appeared to be whip marks. "Someone will be over to check on you tomorrow." He said as they flooed away.
James sat Sirius on the sofa in the living room that they arrived in and he and Remus went to find the kitchen to get some tea. "I'm gonna kill Peter." James muttered.
"Just remember that Sirius got the worst end of this deal, poor sod." Remus said quietly. James nodded, he hadn't really thought about how his friend might be feeling. Madame Pomphrey had told them that although Sirius had all his memories he was still effectively a toddler and should be treated as such, the more tired he was the more childlike he became so he wouldn't be as guarded about his secrets. His younger personality would argue against his memories of how to behave so the two teenagers had to re teach him right and wrong but he would remember things like reading and writing, just his writing wouldn't be as neat. Sirius was half asleep when they went back into the other room and Remus handed him a beaker of warm milk. "Ank oo." Sirius mumbled and Remus gave him a smile.
"Sirius, What are those marks on your back from?" Sirius scowled, James noticed that he somehow managed to look adorable whilst doing so.
"Me speak to muggle." Sirius said,
James frowned when the toddler didn't continue. "And..." He prompted.
"Father punish me." Sirius mumbled, his older self battling against letting this information out.
"How?" Remus asked, part of him already knowing.
"Whip..." Sirius whispered. James had to take a deep breath to calm himself, all he wanted to do was kill Mr Black.
"Siri... Has he ever whipped you again?" Sirius didn't reply but the way he buried his head in James' shirt was answer enough. James sighed, pulling the toddler closer and stroking his hair. "Okay little guy, time for bed."
"Not little!" Sirius protested sleepily, "Don't call me 'ittle!"
James gave a small smile. "Okay, Sorry." He picked Sirius up and carried him to the main bedroom, transfiguring one of the chairs into a cot. Placing Sirius in the cot he realised the boy was fast asleep so he cast a few charms that let him hear everything that happened in the room, just in case Sirius had any nightmares. Sure enough an hour later they head screams coming from the bedroom, Remus ran in there and quickly woke Sirius who was screaming and whimpering in his sleep. "NO! Sowwy Father!"
"Siri! Sirius wake up!" Remus said, shaking the child awake, "Hush, it's okay, he can't get you now.." He whispered, picking Sirius up and hugging him. "You're okay now." He repeated before carrying Sirius through into the living room and sitting on the sofa next to James.
"Sowwy." Sirius mumbled.
"Don't be sorry." James smiled, "It's not your fault… Siri, did you ever have nightmares when you were older…. When we were in the dorm?" Sirius bit his lip before nodding and burying his head in Remus' chest. Remus stroked the boys hair to try and get him to sleep. James left Remus and Sirius on the sofa and went to look around the house.
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