Disclaimer: Harry Potter is owned by J.K. Rowling. I unfortunately don't own it.

To change the future for a better past

1978 Welcoming feast

James Potter was sitting at the Gryffindor table with his friends Sirius Black, Remus Lupin and Peter Pettigrew. It was the welcoming feast to their final year at Hogwarts and it was 1978 and James and his friends were going to enjoy their last year at Hogwarts as much as they could. They were trying to figure out where McGonnogal was because she wasn't up at the head table like she usually was. Just as they were about to start talking about it, Dumbledore stood up. The sorting had just finished.

"Welcome, welcome back to some of you and to others welcome to the start of your magical entertainment. I would like to remind you of a few things that you have no doubt some of you have forgotten-" he looked over at the marauders, they waved back at him cheerily, "- and Mr Filch would like me to remind you of his ever growing list of forbidden items and also about the no magic in the hallways rule. Now I am sure you have noticed the absents of Professor McGonnogal. Yes I thought as much. Now we are very lucky to get this chance. I think a little history lesson is in order, yes I know you don't feel like learning now but I will try to make it as fun as possible. Now when the founders built Hogwarts they installed a time travelling portal where if anything in the future got too bad then a portal would open and the seventh years of around 20 years in the future to help to change it. I have been told by Professor McGonnogal that when she spoke to the future her, the future was bad but not overly so. She said that there are many things that need changing though. Now as you may have figured out already some of these children may be your children from the future. I have been told that by the end of the year all the information needed to change the future will be given to change the future but give them time to explain and gather up their wits. Now the class of 1997 will be here soon and I want you all to refrain from throwing every question you can think of at them. You may see some familiar faces amongst the staff and I wish for you treat them with respect. According to future McGonnogal they have been through hell and back, for a certain member of staff that is literally. Now I welcome class of 1997." Dumbledore said as the great halls doors flew open revealing the future children.

Outside the great hall in 1978

The class of 1997 was waiting outside the great hall in 1978. Lilith Potter was holding Sirius' hand as she was pacing dragging him along with her.

"Linth, sweetie please. Everything is going to be fine. They'll love you, I promise." Sirius said halting her pacing and making her look at him. He took her face between his hands and gently kissed her lips. He pulled away before he got to wrapped up in her as he usually did. It was a well known fact in 1997 that Sirius Black innocent ex-convict and Lilith Potter The Girl Who Lived, were together and were usually overly sweet with each other. In 1997 they had house unity and there were no house rivals. Everyone got along just fine. The would be Death Eaters began to see the horror of what Voldemort was doing and chose not to follow in their parents footsteps, instead they joined the light side and were trying to defeat him. They knew the only person able to defeat him was Lilith Potter. But they knew to be able to defeat him she was going to need her parents to give her the training only a Potter knew about. It was no secret either that the Potters had many powers that they chose not to flaunt them. The secrets about the powers however were big and nobody not even the best friends of a Potter knew about them. Only a Potter by blood or if you married into the Potter line were you able to gain these secrets and as the last of the Potters was Lilith, so Lilith never knew any of these secrets and unless they got her parents back, she never would.

"Alright, everyone knows that they are not to reveal any truthful information to the Death Eaters that are in the school at the moment and the ones we know will become Death Eaters?" McGonnogal asked. Once the students nodded she carried on. "Alright also know that only a select group of people are to know about Sirius and Lilith's relationship and about the fact that Lilith is the only one able to defeat Voldemort." Once again everyone nodded. Lilith turned around to give Sirius one last kiss before going to her place at the front of the line. As head girl and Neville being head boy, they had to lead the rest of their class in. Lilith heard Dumbledore say welcome class of 1997, the doors opened and she and Neville led the way into the great hall.

The Great Hall

Finally the long awaited time was up and the school could see the future children, as they had all unknowingly dubbed them, came through the door. First came the teachers and if anyone were to look in the hall at that moment they would see a very similar expression on everyone's faces and they all looked remarkably similar to a goldfish. Next came the students, at the front of them was a girl and a boy. Presumably the head boy and girl. No one could get a good look at the girls face because she kept her hair covering it but the boy looked a lot like Alice Prewett and Frank Longbottom. Once all the students were at the front of the room Professor McGonnogal went to her seat next to the headmaster and the other Professor McGonnogal turned to face the hall. She looked older but she still had the same strict face. (Ok from now on the people who are in the future as well as the past will be in italics for the future)

"Hello school." McGonnogal smiled. She looked at some of the faces and looked at those she hadn't seen in a very long time. She sighed quietly to herself and turned her attention back to the hall. "Now I'm sure you all want to know who all these people behind me are so I'll let them take over." McGonnogal smiled and it shocked the majority of her past students. She turned and stepped to the side, "I introduce Professor Severus Snape Head of Slytherin house." At that explanation the hall turned dead silent. Very slowly the clapping started.

"I introduce my students Draco Malfoy, Mr Vincent Crabbe, Mr Gregory Goyle, Mr Theodore Nott, Miss Pansy Parkinson, Mr Blaize Zambini and Miss Daphne Greengrass." They all stepped forward as there names were being called.

McGonnogal stepped forward and spoke again, "I introduce Professor Pomona Sprout Head of Hufflepuff house." The clapping started up more this time and then Sprout stepped forward to introduce her students.

"I introduce my students Miss Susan Bones, Miss Hannah Abbott, Miss Rose Carter, Mr Zacharias Smith, Mr Justin Finch-Fletchley, Mr Ernie McMillan and Mr Michel Corner." Again they all stepped forward just as last time.

"Now I introduce to you Professor Fillius Flitwick, head of Ravenclaw house." She said stepping back again.

"May I present my students Mr Terry Boot, Miss Padma Patil, Mr Thomas Powder, Miss Amelia Arrow, Mr Luke Evergreen, Miss Eliza Turner and Mr Arthur McCollon." Flitwick squeaked.

"And lastly may I introduce the head of Gryffindor Professor Remus Lupin," McGonnogal said stepping back smiling as the Marauders whooped and cheered while a very read faced 17 year old Remus Lupin tried to stop them.

"May I introduce my students Mr Dean Thomas, Miss Hermione Granger, Mr Ronald Weasley, Mr Seamus Finnigan, Miss Lavender Brown and Miss Parvati Patil." Professor Lupin said stepping back.

"Now I introduce to you the head boy and girl of 1997 Miss Lilith Potter and Mr Neville Longbottom both of Gryffindor house." The clapping of those names was big. The Marauders were clapping like mad and it made Lilith smile.

"Finally I introduce to you Professor Sirius Black we thought we'd help make history of magic better this year as it is in the future. Now there is no one falling asleep in the lessons." There was dead silence after this last announcement and everyone turned to look at Sirius at the Gryffindor table. Sirius looked around and exclaimed,

"What are you looking at me for I haven't done it yet! Look at him." He told them pointing to Sirius. Everyone looked at him and he raised his eyes as if to say yes. Everyone looked away and waited for Dumbledore to give them food. The future kids were dismissed and told to go to their house tables. The Marauders waved over at Ron, Hermione and Lilith. They sat down opposite them and smiled and soon the Marauders were asking questions.

"Why did I become a teacher?"

"Am I a good dad?"

"Are you going to tell us anything about the future yet?"

"What's it like in the future?" Were just some of the questions asked.

"Wow stop ask questions one at a time, okay. I can't hear you when you talk at once." Lilith said smiling. She was glad she was excepted by her dad. Now all she had to do was to be excepted by her mum. She glanced down the table at her and found her in discussion with Neville, Alice and Frank Longbottom. Or at least Alice Prewitt soon to be Longbottom. Her eyes found her dads again and she smiled when she saw the mischief in them.

"Am I a good father?" He asked. Lilith looked down before taking a deep breath and answering.

"I wish I knew. I'll tell you more later but the basis of it was that you and mum were killed by Voldemort when I was a year old. I only remember you telling mum to run with me and that you'd hold him off and then mum pleading with Voldemort to kill her instead of me. That's all I remember of you and I got those memories because I was near a dementer." Lilith answered. When her eyes found her dads again she saw pain in them and love.

"I'm so sorry I left you. Where did you go? To Sirius?" James asked.

"No, erm, it's not really my story to tell you'd have to ask Sirius for all the details but I actually went to my mums Muggle relatives. Sirius was how shall we put it, preoccupied."

"Talking about me I see." Sirius said laughing quietly when Lilith jumped. She turned around and hit him lightly in the chest.

"Don't do that." She scolded him.

"Why don't you all come to the rooms I'll be staying in after dinner, Lilith knows where they are. Bring Lily as well." Sirius told them and walked back to the staff table. James looked after his older best friend worried. Sirius seemed to have changed a lot.

Staff Table

Once Sirius got back to the staff table he sat down. McGonnogal looked at him sternly.

"I hope you weren't giving them prank ideas Sirius Black." She warned him. Sirius looked at her with a raised eyebrow,

"And make my job harder? No thank you." He told her. McGonnogal looked at him shocked. McGonnogal looked at her past self amusedly.

"He's changed a lot. He's not the care free man he once was." She told her past self.

"And what could have possibly changed Sirius Black so much. Because I know for a fact that it can't have been something little." McGonnogal said. Sirius didn't say anything while Remus finally looked up.

"It wasn't." He told her.

"Well what was it?" Clearly she was not about to give up.

"The death of my best friend and having another best friend as a traitor. Going after the traitor and then he starts shouting that I killed James and his wife and then he blew up the street killing 13 Muggles and cut his finger off to make it look like I killed him. Then being chucked in Azkaban for 12 years without a trial or a questioning, until I finally escaped in Linth's 3rd year. During all that I left Remus to think that 2 of his best friends were dead and one was a traitor. Finally I had one year on the run before I caught the traitor but not before Voldemort came back." Sirius finally exploded quietly to the staff table. All the people from the past looked at him shocked.

"That happened?" McGonnogal asked finally asked hoping to God it was not true and just a joke. At Sirius' nod her eyes grew wider.

"How did we not know who the traitor was?" Dumbledore finally asked.

"I was the original secret keeper but I convinced James and his wife to change to Peter because no one would ever suspect him, little Peter Pettigrew. I would play the decoy and as James' best friend everyone would think I would be the secret keeper but even if I was tortured or given Vertiserum I couldn't give up their location. It was the perfect plan except for Pettigrew was the traitor and sold James, his wife and Linth out to Voldemort. Voldemort came to Godrics Hollow on Halloween 1981 and killed James, his wife and when he turned his wand on Linth and cast the killing curse, it didn't work the spell backfired onto Voldemort making him weak and he fled. Lilith is the only known survivor of the killing curse and Voldemort. That's why she's on Voldemort's hit list. Though that's not the only reason. There is the reason why he came to Godrics Hollow that night. I arrived in time to get Linth out of the house and then Hagrid came and told me that Dumbledore told him to bring Lilith to him. I argued at first but in the end my need for revenge on Pettigrew won out and I handed her over. I've never forgiven myself for what I did that night. I condemned her to a life of abuse and rape. But that's a story for another day." Sirius said. Both McGonnogal had tears in their eyes and Remus was looking downtrodden. Dumbledore's eyes had lost their twinkle and Snape wasn't even sneering.

"Sirius how many times have I told you not to blame yourself for that. For Gods sake man. Get it through that head of yours. I'll meet you in your room with everyone later. Stop brooding all of you. What's done is done. There's no point dwelling on it. So stop otherwise I will make sure that if you ever want to have children then you won't be able to got it Sirius Black?" Lilith questioned. Sirius nodded but then grinned.

"Yes but baby if you do that then you can't have children either unless you leave me. And you and I both know that isn't going to happen." Sirius whispered quietly to her. Lilith bit her lip. She meant to talk to him about this earlier but she didn't get the chance to.

"Yeah about that. I need to talk to you soon privately." Lilith whispered then left the staff table to go back to the Gryffindor table leaving Sirius in a state of shock.

"Is he okay?" Flitwick asked looking at the older version of one of his students.

"I don't actually know. I haven't seen him like this before." Remus said looking at him cautiously.

"Oh I think Sirius is quite alright just got the shock of a lifetime." Dumbledore said cheerfully having heard the entire conversation clearly. He was quiet happy about what had happened.

Eventually Dumbledore sent the students on their way and Sirius left to his quarters to find his younger self James a younger Remus and thankfully no Pettigrew, he also saw Lilith Ron and Hermione along with Lily. He smiled as he entered the room, completely aware of the conversation about to start…

This was my first try at a story how did I do. Please give me some reviews.