Disclaimer: Rowling owns the Blacks in all their beautiful, inbred glory.

Summary: Sirius was raised like all Blacks, so what happened to change him so much at a young age that the Hat put him in Gryffindor? Focuses on Sirius and Regulus in pre-Hogwarts years. Oneshot.

Rating: PG, K+ for minor violence and brief descriptions bloody cuts

Genres: Family, Drama

Characters: Sirius, Regulus, Walburga

Becoming a Blood Traitor

Sirius saw Muggle children playing. It looked more fun than having to stand straight and immobile beside his father while wearing too-tight shoes. One child fell and skinned his knee. Sirius watched with interest. His parents always said pure blood was the best, and he was curious about what dirty blood looked like. The strange thing was…it looked like exactly the same thick redness Sirius' or Regulus' bled when they roughhoused too hard.

Confused, Sirius asked his mother about it. She shrieked with outrage at the suggestion that purebloods had anything in common with Muggles. Sirius asked if maybe it wasn't the colour of the blood, but something in it. He asked, intrigued, to see or feel what the difference was; what it was that made the Blacks better.

His mother smacked him and locked him in his room for his insolence.

Sirius knew the punishment was supposed to make him accept her word without proof. He wondered if the reason she didn't offer evidence was because there wasn't any. Maybe the Blacks weren't better at all, and people only agreed with them because they punished those – like Sirius was being punished now – who questioned their claim.

It was a terrifying thought, to imagine so many people were lying to him. Worse, they were lying to Regulus, too. Sirius told Regulus about his suspicions because he loved his brother and didn't want him to be tricked. How did Regulus repay him? By telling Mother.

This time, Mother smacked Sirius harder.

Sirius was cleaning the blood – the supposedly superiour blood – off of his lip in the bathroom when Regulus came in.

"What do you want?" Sirius snapped.

"Please, don't be angry," Regulus pleaded. His eyes, a less stormy grey than Sirius', were wide and earnest. "I didn't know she would do that. I thought she would cure you."

"Cure me?" repeated Sirius in disbelief.

"Well, someone's obviously Confunded you or slipped you a potion." Regulus tugged on his black hair, a less shiny black than Sirius', nervously. "I mean, everyone in the family says purebloods are the best. Our parents, cousins, aunts, and uncles can't all be mad, Sirius. There must be something wrong with you."

Sirius laughed, but Regulus didn't think he sounded happy. "Something's wrong with me, eh? Been listening to Bella, have you?"

Regulus shook his head. Bellatrix had frightened him ever since he'd seen her using her magic to dismember a bird in the backyard, and he didn't speak with her if he could avoid it. "I'm worried about you, Sirius. You wouldn't be having such mad thoughts if you weren't ill."

Sirius began to wonder if that was true. He wondered if there was something wrong with him making him question what everyone else accepted. For months, he looked through old family albums trying to find features marking a Black's face as more worthy. Try as he might, he found nothing.

One day, Uncle Cyrus came over ranting about something to Mother and Father. Sirius crept out of his room and watched in fascinated horror as he saw his mother burn Andromeda's name off of the tapestry. Andy was his favourite cousin. She didn't smash his toys, like Bella did, or sit in front of a mirror instead of playing fun games, like Cissy did.

At dinner, Mother announced to Regulus and Sirius that Andromeda was no longer part of their family. She was a blood-traitor, and if they saw her in public they weren't to acknowledge her.

When Sirius asked what made her a blood traitor Mother told him she'd married a Mudblood because she didn't understand what made purebloods superiour.

In that moment Sirius realised he wasn't the only Black unable to see the variations between the bloods. Andy had the same feelings, and Sirius had always liked her.

Maybe there wasn't something wrong with him after all.

Regulus didn't seem to agree, if the event two years later was any indication.

At a party – no, not party: 'social function' – at the Malfoy Manor, he followed Sirius out onto a balcony.

"Sirius?" Regulus' brother didn't reply. "What are you doing out here? You should be in there making friends."

Sirius snorted. "Making connections, you mean."

"Connecting what?" Sirius did turn around this time, and saw Regulus' brow furrowed in genuine confusion. He truly was too young to understand politics yet, and that alone made Sirius feel warmth towards him.

"Never mind."

"If I were you, I'd try to make friends now so I'd already have them when I got to school. You're going to be in Slytherin with them next year, you know." Regulus commented, sounding both envious and fearful of being alone. He noticed his remark made Sirius smile, but it was another of his unhappy ones. Regulus had difficulty remembering the last time he'd seen Sirius actually happy.

Unbeknownst to Regulus, the cause of Sirius grim amusement stemmed from the assumption about him being 'in Slytherin' rather than 'at Hogwarts.' Sirius was growing more and more aware that in their social circle people failing to encourage power for the purer wizards weren't worth mentioning. People like Andromeda.

"What if I don't want to be in Slytherin? They're no fun anyway." The blasphemy of the statement was worth saying simply for the sake of seeing Regulus' incredulous expression.

He gasped, "But you…you have to be! Don't you? After all, every Black has been. It's in your blood." Regulus recited a familiar phrase told to them by their mother, "'Blood is stronger than all things; stronger than pain and fear and desire. Blond conquers all weaknesses.'" Regulus wasn't sure what conquer meant, but could at least surmise the gist. "You can't stop yourself from being a Slytherin just because you want to. Your blood will always win."

Sirius scowled at him. "Get lost."

"What? Why?"

"Just go away."

Looking hurt, and a bit angry, Regulus obeyed.

It wasn't as if Regulus had been condescending. What upset Sirius was the concern that he might be right. Sirius rolled up the left sleeve of his expensive robes and stared at his pale, smooth arm. He walked over to a statue of a gargoyle and slammed his exposed arm hard against the jagged wing so a shallow gash appeared on his limb. Sirius held his right hand open beneath the wound and allowed some warm, crimson liquid to fill his palm. He reached for his magic and tried to use it to shape the tiny round puddle into the likeness of the crescent moon above him. The fluid wiggled as if I wanted to move, and some droplets began clumping together, but they wound up in a shapeless puddle in the centre of his hand once more.

Sirius swore and wiped the blood on a stone railing. He didn't like it being suggested that his desire, his will, couldn't change something, including his blood. Someday, he'd prove his will was stronger than his blood.