Chapter IV- Sibling Rivalry

Sirius's brother arrives, but he dares anyone to recognise the connection.

September, 1972.

When they start second year, a boy arrives, Regulus, who's the spitting image of Sirius. They have the same handsome, careful features, all razor sharp contours and cut-glass, but Regulus's face is longer and more pointed. His hair is the exact same shade of charcoal as Sirius's, but it's shorter round the ears and piled high on top, tousled and rolled back like waves. There's a delicate air to Regulus; his shoulders are narrower, he's a slighter build, more pristine, and he looks like one gust of wind could knock him over whereas Sirius looks like he could weather the storm.

The resemblance between Sirius and Regulus is breath-taking but there's a hex on offer for anyone who mentions it. James needs to ask, though- it's his persistent curiosity- and he reckons he can get away with it because he's Sirius's best friend. So he ventures for it one day, when they're in their dormitory and James is sitting crossed legged on his bed and Sirius has artistically draped himself across his own. James musters up his courage and asks, "the boy in first year, the one with your surname, is he a cousin, or is he your brother?"

There's an audible intake of breath in the dormitory and Remus and Peter wait.

The thunder in Sirius's raincloud eyes rumbles and he glares up from below his eyelashes. "My brother," he huffs.

Remus sits up on his bed and scoots to the end, until his legs dangle over the edge, and James looks startled. "Regulus?" He asks bluntly. "I remember his name from the Sorting."

"And?" Sirius growls.

"Well, it's been three weeks," Remus points out, "and you haven't spoken to him once."

He scoffs contemptuously. "I don't speak to him at home, why would I speak to him at school?"

James doesn't want to laugh, but the idea of Sirius and his brother wandering through their stuffy Islington palace in silence is rather funny. "He doesn't look too good, mate."

"That's because he's a Black." Sirius replies waspishly.

"No," James begins again, determined to make his point. "I mean, he looks sort of…" he weighs his words to find the most suitable, "sad." James says tentatively, and Remus throws him an apprehensive look.

"He's a miserable git. Probably moping because Mummy isn't here to tie his shoelaces for him." Sirius starts scuffing his shoes on the floor and James does the wise thing not to point out that he's seen Regulus do the exact same thing in the corridors as he waits outside his classes.

"Yeah, well, maybe he could do with a brother." James would love a little brother, and he feels somewhat irritated that Sirius could be so callous towards his own family.

"He needs a good shake," Sirius sits up arrogantly and folds his arms. "Reg is pathetic, I'm not getting involved." And with that, Sirius huffs out of their dormitory.

They must have been friends once, James thinks- because otherwise Sirius wouldn't have ever given him a nickname, and for the rest of their Hogwarts career, James never once hears anyone else call him Reg.

# # #

Seven-year old Regulus creeps to the top of the house and presents a squashed napkin to his brother. "Why can't you eat with us?" He asks, as Sirius unwraps the napkin and frowns at the lone bread roll inside.

"Because I don't want to." Sirius replies aloofly, tearing a chunk from the miserable-looking roll.

Regulus stands nervously beside the door. "Why not?" He says.

Sirius shrugs. "Because mum's stupid."

"Why do you think she's stupid?" Regulus creeps closer into the room.

Sirius flounces back onto his bed, sitting up so that he can look out the window. The rain beats against the window panes, counting down like the ticking of a clock. "Because of what she tells us."

"What do you mean?"

Resigned to the fact he will not be left alone, Sirius gets back up and walks around the room to face Regulus, who's taken up a cosy position perched on the other side of the bed. "All that pureblood nonsense." Sirius explains, with a tired air. "She keeps talking like purebloods are better than everyone else, but why? What's wrong with muggles?"

"They're dirty and stupid." Regulus replies instinctively, repeating the opus he's been bidden to memorise.

Sirius looks almost pityingly at his brother. "Really, Reg? We've never met any, how can we know that?"

"Because mum says so."

"Exactly, and mum's stupid!" Sirius repeats with a resigned sigh. "She's a mad old hag and she hates everyone-"

Regulus is staring at the door with wide eyes. "Sirius." He interrupts.

Sirius ignores him. "-who isn't pureblood but if you ask me, I think purebloods are worse than anyone else-"

"Sirius!" Regulus almost shouts. Sirius follows his eyes, staring at a spot behind him, and he turns to see Kreacher the house-elf skulking outside the doorway. Kreacher's mother has recently died, and as such Kreacher is now the sole house-elf to the noble and ancient House of Black- a hallowed role he's taken with much enthusiasm. He snarls cruelly at Sirius before muttering something to himself and disappearing into the shadows.

Sirius's face drains of colour and his eyes stare in panic. The temperature in the room seems to drop a few degrees. "How long was he there?" He eventually asks.

"Long enough."

"Why didn't you warn me?!" He turns on Regulus with a frantic fire in his eyes. "He's going to go and tell mum and she'll be furious!"

Regulus jumps from the bed, startled at the look on Sirius's face. "I couldn't just tell you Kreacher was there, that would be strange!" He argues.

Sirius sighs heavily before he nods dolefully in agreement, but there's still a haunted look in his eyes as if he fears for his life.

"We need a secret code that no one knows except us so we can warn each other." Regulus says, laughing uneasily to break the tension.

Sirius scoffs. "Secret code? Reg, you read too many detective stories."

# # #

Eight year old Regulus has been told something he doesn't understand and he finds himself going to his brother for help.

"What does mum mean, when she says 'Slytherin would be proud'?" He asks Sirius, who's sitting up on his bed sulking and scuffing his feet on the wooden floor.

At the sound of Regulus's voice, the scuffing stops and Sirius turns his head to look towards the door. "Slytherin's some demented old wizard who wanted to rid the world of mudbloods." He tells Regulus. "He's one of the founders of Hogwarts, that's why there's a house named after him."

Regulus sits on the bed with his back to Sirius. "So, why would he be proud?"

"I don't know." Sirius replies carelessly, turning to look out of the window again. He's spent so much of his time staring out of that window that he's memorised every fleck of dirt on the panes. "Did you do something stupid? Like spit on a mudblood or burn a muggle?"

"What's it like to be a Slytherin at Hogwarts?" Regulus asks.

"I don't know, Reg. I'm not at Hogwarts yet, remember." Sirius points out. "And I'm not going in Slytherin, anyway."

"What's wrong with Slytherin?"

Sirius frowns. "Well, everyone's in Slytherin."

Regulus looks back, his eyes filled with an innocence that Sirius wants to laugh at. "So you'll be with all our family!" Regulus reminds him. "Narcissa, and Bellatrix and Andromeda!"

"I don't want to be with them, they're all idiots."

"Sirius-"

He's in full flow and ignores Regulus's interruption. "And Bellatrix is mental and they all think that it means something to be pureblood and they all laugh at muggles, but really, Reg, what's so wrong with muggles?! I keep asking but no one can tell me!"

"Sirius!"

Sirius feels an elbow jam sharply into his back. "What?" He growls, shoving his own elbow into Regulus's back before turning to face him. His attention is caught by a shadow flickering against the wall in the hallway, and the creaking of the wooden floor. Sirius can tell from the way the shadow falls that it is not their mother- it's a male figure, he's sure- and it is not their father, it's far too short, so it must be their Uncle Alphard, who has been staying with them over the week to attend business at the Ministry.

Regulus must have seen him too. "Do you think he's going to tell mum?" Sirius asks quietly.

"Probably." Regulus shrugs. "I bet you wish we'd invented that secret code."

"Shut up, Reg." Sirius elbows Regulus in the back again and the brothers sit in silence for a moment.

"Sirius," Regulus suddenly asks, his voice grave. ""Why can't you just ask to be put somewhere?"

"What?"

"At Hogwarts." Regulus clarifies.

Sirius laughs to himself. "That's not how it works. You put this hat on and it sorts you into your house, that's why it's the Sorting Hat. It looks in your head and decides where you should go from that."

"But Sirius," Regulus says. "It's a hat. Why do you have to listen to what a hat says?"

"I don't know. It's just one of those things, isn't it?" Replies Sirius. "I don't want to go in Slytherin, I'd go anywhere else if I could, but I'm not clever enough for Ravenclaw, I'm not brave enough for Gryffindor, and I'm not nice enough for Hufflepuff."

Regulus frowns in confusion and he can tell that Sirius doesn't want to answer any more of his persistent questions, but he just doesn't understand why Sirius couldn't go in whichever Hogwarts house he wants- Sirius is his brother, and he's the cleverest, bravest, and nicest person Regulus knows.

# # #

The parties are not what nine year old Regulus would consider fun, but he goes along with them, and at least he has a better time than his brother does. They stand together, following their parents around the room and greeting their parents' friends. They're the heir and the spare; Sirius is presented first, the firstborn heir and the better son, and he scowls at them with conceit. Regulus smiles politely and knows that they'll all remember Sirius, but they'll forget Regulus's name before the evening is over.

"Mum said we can talk to the Rosier twins." He tells Sirius, who is pulling at the buttons on his waistcoat as if they're digging into him like pins.

"I don't want to talk to them. I don't want to talk to anyone." Sirius says scathingly, folding his arms.

"Why not?"

"Because they're all the same!" He replies, sounding irritated.

Their mother is talking with another lady, one who is just as tall and severe and full of sharp laughter and ingratiating smiles. Regulus points at the two blonde-haired children standing beside the two women. "Mum likes the Rosier twins. I bet they're not the same as everyone else."

Sirius's laughter is hollow. "I bet they think mudbloods are filthy. I bet everyone here thinks that."

Regulus catches a snatch of their conversation and the women turn to look at the two brothers. "Sirius, what does 'betroth' mean?" Regulus whispers.

"I don't know." Sirius's eyebrows crease in confusion. "Why?"

Regulus shrugs and looks around the room at the rest of the people gathered there, their parents friends, all dressed up in feathers and velvet and sparkling gems. Does everyone here think that mudbloods are filthy? If so many believe it, surely it must be true? "Sirius," Regulus asks. "Are mudbloods filthy?"

Sirius looks down at his little brother but there is no hint of a scathing scowl on his face. "I don't know." He admits. "But just because mum and dad say it, why should we believe it?"

# # #

Ten year old Regulus is excited for his brother to come home over the Christmas holidays. It feels like it's been a lifetime since he and Kreacher dropped Sirius off at Platform Nine and three-quarters on the first of September and the days he's had to pass alone in Grimmauld Place have seemed twice as long as usual.

There has only been one letter from Hogwarts, arriving the day after Sirius left, but it was from their cousin Narcissa and told of Sirius's sorting. Their parents barely spoke of Sirius for some weeks after. Then several more letters arrived from Hogwarts- official looking letters from the teachers with the Hogwarts crest stamped on the back- and they were all tossed into the fire. There have been no letters from Sirius and so Regulus assumes that Sirius has just been too busy to write to his little brother, but he can't wait to hear all about Hogwarts. He cannot wait to hear about Sirius's new friends, he cannot wait to hear about the spells he has learnt and the potions he has brewed. Most importantly, though, Regulus cannot wait to hear what the other children are like; what the halfbloods and the muggleborns are like.

But Sirius never comes home for Christmas. It isn't until the summer that Regulus sees him again, but he and Kreacher do not accompany him home from the station, and when Sirius arrives at Grimmauld Place he runs to his room, slams the door, and doesn't come back out.

# # #

Eleven year old Regulus expects school to be like home, with a brother that barely acknowledges his existence- and that, he thinks, he could cope with. But the indifference from Sirius is nothing compared to the attention from others. He sees the looks shared between the teachers first, then he hears the whispers along the house table and in the common room. There's a shared feeling that spreads between his housemates when the Sorting Hat cries Slytherin, because they all expect him to be like his brother; they expect him to be a rebel. They expect him to cast off the pure-blood elitism that the others believe in and they expect him to be as disparaging of Slytherins as Sirius is.

It isn't until Regulus arrives at Hogwarts that he starts to despise it- he's always Sirius's little brother. He is always being compared against Sirius. And its Sirius's complete disregard of him that makes him hate the similarities; all he wants to do is prove that he is nothing like Sirius.

Sirius never shows an interest in Quidditch so Regulus decides he will make the house team. His slight frame makes him quick and nimble on a broomstick, and when he comes home over the summer after his first year and Sirius sulks in his bedroom, Regulus asks Kreacher to hide tiny gems all over the house and by the time he returns to Hogwarts in September, Regulus is like a magpie and he can spot anything that glints and shines; he is the perfect seeker.

Sirius hates his pureblood ancestry and so Regulus studies their family tree until he knows it by heart and he's never know his mother to be prouder of him. He paints their family crest on his bedroom wall and he drapes Slytherin banners across the furniture and he keeps clippings from the Daily Prophet of impressive shows of Dark Arts. Everything that Sirius hates, Regulus plasters onto the walls of his bedroom.

At Hogwarts he joins the right crowd, makes friends with the right people, agrees with the right things- all traits that would make his parents proud. They're not necessarily things he would choose to do but he's too busy proving he isn't like his brother to bother about what he really believes in. He sticks on the right side of the school rules and he never gets caught, and he keeps his head down to avoid detentions whilst his brother whiles away evening after evening in a teacher's company. Until eventually, they share nothing but a surname and the school seems to forget they're even related.

But that's why they're exactly the same. They'll do anything to prove people wrong.

And no-one else notices it except James Potter, because he looks at people like they're books to be read and he unravels them, deciphering the writing that is scrawled across their hearts. He knows Sirius Black does not deserve his name's reputation, he knows Remus Lupin is not as calm as he appears, he knows Lily Evans is not a clueless muggleborn, and he knows Regulus is not the antagonist his brother presents him as.

Shortly after the start of their second year, and just a few days after that first conversation in their dormitory when James had asked Sirius about his brother, James sees Regulus waiting outside the transfiguration classroom.

"Hi, Regulus." James offers. By some miracle- or rather, a lunchtime detention- James is without Sirius. He smiles at Regulus and takes the moment to look at him carefully. Regulus's eyes hold the same haughty look that James has so often caught in Sirius's and a sneering scowl rolls along his nose- but while Sirius has that single sunbeam that breaks through his raincloud eyes and softens his conceit, and the goofy grin that's charming and makes Sirius seem human, Regulus's eyes are flat black, like tar, and hauntingly eerie.

Regulus, the boy who looks so much like James's best friend, is torn between being polite or staying alive. Because if he doesn't reply, he's rude, but if he does and Sirius finds out, Sirius will curse him. Regulus opts for a stifled nod- it's the most he can manage- and it surprises James. From the way Regulus had stared at him, from out of those devil's eyes, and from the way Sirius spoke of him, he'd braced himself for a curse. He'd been wrong to expect one.

# # #

"I saw Regulus in the corridor the other day, outside the transfiguration classroom." James tells Sirius. It has now been a month since Regulus started school, and Sirius has still not spoken to him. "He seems alright."

Sirius huffs dramatically. "He's not. He's an idiot." He flips himself over on the bed so he's facing away from James.

James shrugs, addressing Sirius's sulking back. "Well, maybe you just don't know him that well."