Title: Surprise! You Have A Son!

By: Spiritraven

Disclaimer: I don't own Harry Potter or Buffy the Vampire Slayer.

Warnings: Slash and maybe some violence.

Pairings: Angel/Xander, Sirius/Severus, and more later on.

Chapter One:

Xander has seen a lot of strange things in his life, but a big black dog falling out of a portal wasn't one of them. The dog was hurt and he had to help he had the gut feeling that this wasn't a normal dog. And Xander learned the hard way to always trusts his gut feelings.

"It's okay boy I just want to help." Xander told the growling animal as he got closer. He held out his hand smiling so the injured animal could sniff him. "It's okay you can trust me."

The dog limped closer sniffing his hand then gave it a small lick. Xander slowly got closer and checked the dog to see wasn't that hurt. He wasn't a vet, but he thought the dog should be fine. "You just need some food and rest boy. You can come home with me." He picked the animal up for such a big dog he didn't seem to weigh much.

Sirius remembered going to the Ministry to save Harry only to fall into The Veil thinks to his insane cousin. Now here he was not having any idea of where he was, but the place gave him a bad feeling. There was evil magic around here. He would stay as Padfoot until he learned where he was and how to get back home. By the accent of the boy he was in America somewhere.

"My dad is suppose to be over so I hope he doesn't mind about you." Xander was excited since he hadn't seen his real father in over three months because of the mess in the Wizardry World. Xander was sent to the Hellmouth to live with his squib aunt and her muggle husband. The only person who knew truth about Xander was Willow. "My dad doesn't like dogs much can't really blame him though. I really don't know the whole story only that he hates big black dogs. And that's what you are a big black dog. Oh will I can handle my dad and I'm sure you both will get along just fine given time."

Padfoot was wondering when the boy was going to shut up. It wasn't really talking more like babbling. The boy smelled nice though and he reminded him somewhat of himself. Bloody hell the boy could even pass as a Black with his dark hair and eyes. Sirius if this boy might be of his family with their habit of sending their squib children away.

"Here we are." Xander opened the door to his apartment and found his father sitting on the couch with a book in one hand and a cup of tea in the other. He knew something had to have went wrong by the look on his father's face. "Hey dad everything alright?"

Severus Snape looked up at his son and felt his eyes widen when he saw the dog in Alexander's arms. "Black."

"Huh, oh yeah the dog." Xander thought his father meant the dog. "He fell from a portal. It was so weird."

"No, that is no dog." Severus stood up and grabbed the dog from his son placing him on the floor. "Everyone believes you to be dead, Black." Hearing from Dumbledore that Bella killed Sirius when she sent him through the Veil and being blamed by Potter for his godfather's death.

Xander watched as the dog turned into a human man. This guy was from the Wizardry World and his dad knew him, but they were not friends that were for sure. "What's going on?"

"Since when did you have a son, Snape?" Sirius asked after he got over his surprise at seeing the Slytherin and learning his enemy had a son. For some reason that bothered him greatly. "And where are we?"

"Sunnydale, California the home of the Hellmouth." Severus crossed his arms over his chest a smirk on his face. "Surely you know how children are born, Black."

No one in the Order knew Snape had a child or was even married. Something was going on and Sirius planned to find out. By Alexander's age Severus was still a student in Hogwarts when he was born. Surely the Headmaster knew. "I want to know why no one knows about your son."

Severus glared at the Gryffindor knowing that if he weren't careful then Black would learn his secret and he couldn't let that happen. There was too much at stake and he would let nothing hurt his son his only reason at living. "That really isn't none of your business."

"Hey guys did you forget about me?" Xander was getting tired of them talking about him like he wasn't there. "Can you tell me what's going on dad?"

Severus looked at his son and sighed. "Alexander this is Sirius Black, he is a member of the Order and Harry Potter's godfather."

"Sirius Black." Xander knew all about Sirius Black, but it would seem his dad didn't want Black to know their secret. "Nice to meet you."

"Who's your mother kid?" Sirius just had to know the thought of Snape having a kid bothered him. Sirius liked to believe he knew everything about his enemy and once lover. If Snape was really Alexander's father then they were still together at the time. Sirius shouldn't be surprised if Snape did cheat on him, he was a Slytherin after all.

"That is none of your business." Severus wasn't about to let Sirius Black know his secret one that he has kept for so long. He was sure Alexander wouldn't say anything either. "I'll contact Dumbledore to let him know you are alive. Potter is upset over your so called death."

Sirius cursed himself having forgotten his godson and knew he needed to see Harry right away, but this wasn't over. There was something bothering him about Alexander, Snape's son and he was going to find out. "Fire call Dumbledore, I need to see Harry."

Xander went over to a wall and placed his hand on it watching as it turned into a fireplace. He threw in the floo powder and called on Dumbledore the old man's head appearing in the fire.

"Ah, Alexander is something wrong?" Dumbledore asked with worry in his voice thinking something happened to Severus.

"Nah, dad wanted me to tell you Black is alive and well." Xander stood out of the way so the Headmaster of Hogwarts could see Sirius. "He fell from a portal here in Sunnydale. I brought him home and dad told us to call you."

Albus was relieved when he saw Sirius alive glaring at Severus. It would seem he found out about Alexander and wanted to know why Severus kept his son a secret. Albus knew the whole story, but gave his word to keep it to himself. "Then come home Sirius, Harry needs you right now."

"This isn't over." Sirius snarled at Snape and stepped into the flames. Xander turned to face his father.

"It's only a matter of time when Black learns he's your other father." Severus sighed, sitting down. "Then all hell will break lose."

"I'm surprised he didn't figure it out." Xander saw how much he looked like Black instead of his other father. The man must have noticed how much he resembled him.

A small smile crossed Severus face. "Sirius never was very smart. He preferred pranking and mayhem over school work." Sirius along with Potter, Lupin, and Pettigrew were his worst enemies. Lupin wasn't so bad, but he didn't speak up either when they done something bad to him. His only friends were Lucius and Lily who in the end chose Potter. For a while everything was fine and Severus ended up being the boyfriend of Black the wizard everyone both male and female wanted in their beds, but he was his and for awhile Severus was happy.

"What happened between you two?" Xander asked wanting to know what happened between his parents. He saw the hate in Black's eyes when he looked at his father and that really bothered Xander.

Severus took a deep breath and sat back down on the couch. He had never lied to his son having told him everything the moment he believed the younger wizard would understand. "Dumbledore came to your Godfather and I and asked us to join the Dark Lord as spies. We had to keep it to our selves no one besides Dumbledore would ever know the truth. Sirius found out and didn't take it well and I wasn't aloud to tell him until it was too late."

"When you found out you were pregnant with me?" Xander sat down next to his father offering him comfort.

"Yes, Dumbledore agreed I could tell Sirius everything." Severus remembered that night and the hurtful words that were said. "It was too late and Sirius had someone else I wasn't important anymore." It was painful seeing Black and Lupin together that night.

"You're important to me." Xander smiled and hugged his father to him knowing the pain he had to be feeling right now.