1. When Bellatrix's letter came back to his mother, announcing Sirius' terrible Sorting, Walburga Black spent the rest of the day screaming and shouting, breaking things at random and kicking poor Kreacher who followed her around, trying to calm his mistress down. Orion Black had locked himself in his room and didn't say a single word. Regulus, young little naïve Regulus, didn't understand why a hat could tear a family apart, so he dealt with it the only way he could. Looking at the ceiling, he mumbled under his breath. Sirius isn't worth it. Sirius isn't worth it. Sirius isn't worth it… except he was.
2. A single line on the tapestry connected them, but years of misunderstandings and hateful words widened the gap into a gaping abyss with only a single bridge that frayed each time they denied each other until one day, it simply snapped.
3. He would never, ever admit to Regulus, on the pain of death, that it hurt when he saw him wandering around with his Slytherin gang, treating them better than he had ever treated him.
4. He would never, ever admit to Sirius, on the pain of death, that it hurt when he walked past the Gryffindor table and heard him declare that James was the best brother one could wish for.
5. They had both chosen their own paths at sixteen; Regulus the Death Eaters, and Sirius the Order. Sirius called Regulus a callous idiot, and Regulus screamed 'bloodtraitor' at him. In reality, they weren't that different; they were foolhardy, and so painfully young. Too young to be choosing sides in a war they should have had no part in at all.
6. The main difference between the Order and the Death Eaters was the fact that no one in the Order wore masks, and everyone in the Death Eaters did. In public functions, the masks were the pureblood façade of superiority while the blood traitors and half bloods and mudblood laughed and wore their hearts on their sleeve. In the battlefield, the masks were the bone white shapes that covered every one of them, hiding their cowardice. It was so easy to be cruel when no one knew who you are. And Regulus wished with all his heart the Order would do the same too; it was one thing to murder faceless muggles who were like filth. It was another to be cutting down people with faces you recognized; the same hands that brewed brilliant potions in school, the same arms that hit bludgers at you, the same cheekbones as a schoolmate, the same grey eyes that your brother has, and that while you are killing people, real living breathing people, your brother could be dead too.
7. Sirius was born on Samhain, 1959, and Regulus on Beltane, 1961, but the younger brother was so much slighter, and softer spoken, that most assumed them to be quite far apart, especially before they attended Hogwarts. It was particularly fitting, that Sirius was born on the festival for the dead, and Regulus on the festival for the living, because they were just two sides of the same coin, and Blacks were too fierce, and two wild, to not walk that fine line. They always enjoyed playing with fire, which was why it burnt them so badly when things went wrong.
8. Their mother never truly loved them; she was a cold woman, often cruel and enjoyed playing games to make them obedient, which made it so easy for her to transfer her 'affection' from one son to the other. When she went mad, it wasn't out of grief for her two sons, as good as dead, but for the shame they had brought to her name, for she was, until the very end, born and bred a Black. And that was something she had, unfortunately, passed on to both of her sons.
9. Quidditch was something neither of the brothers had a chance to play in their childhood, because Walburga Black thought that sports were uncouth and only for the common, unwashed masses. But both had an innate talent in it that shined when they reached Hogwarts; Sirius, who always too angry, made an excellent beater, with brilliant aim and all the unspent energy poured into his vicious swings that landed far too many in the Hospital Wing with at least three broken bones. And Regulus, who had developed an eye for detail and a knack for slipping away from unwanted attention, became one of the best Seekers Slytherin had seen for years. It also helped that competitive flying gave them both a freedom that they could not afford with their feet on the ground.
10. Sirius started smoking pot and dabbled in coke ever since he was fourteen, fresh from a summer at France with his family and one too many kisses on his lips. He would sit in his room and shut all the windows before either giving himself a shot that would allow him to get high before knocking him out for a few hours of peace, or lighting a joint and inhaling the poisonous gas deep into his lungs, a figure amidst the shadows and smoke.
11. By the age of sixteen, Regulus had developed something of an unhealthy relationship with alcohol, though this was one of his best-kept secrets that he carried to his grave. He doesn't really remember how it started, but all he knows is that suddenly, that one summer after his brother had left, the entire house had become too silent, and he began a game of sneaking all sorts of alcohol into his beverages, after which he would spend the rest of the day holed up in his room, knocking back enough shots to numb him to the point where everything became a foggy, pleasant daze. The rest of the school year passed quite the same way, and by the second half of it, he was alternating between taking hangover and nutrient potions in the morning, drinking through the rest of the day before spending dinner in the toilets, almost turning himself inside out from vomiting bile because there was no food in his guts.
12. He had something of a reputation as boring and studious, and he appeared to be the epitome of tiring perfection: top grades in every subject, Quidditch player, good family, wealthy, in the Slug Club, (It may have had something to do with the previous few things), rule-abiding, never dating, first prefect, then Head Boy, and to those who mattered, junior Death Eater in training and enough wits to keep himself alive. To those who didn't matter, they had a hard time proving that the seventh-year Slytherin Black had nothing to do with the Death Eaters. By all appearances, he had everything anyone could want, and was as about interesting as a block of wood. In truth, he was everything but rule-abiding; he was quiet, yes, but he was also an acerbic and cold bastard, saved from the family madness only through good breeding, and of course, it made it much easier to get away with things like hexing Malfoy's mirror to sing "I'm so pretty," in the middle of the Great Hall at breakfast. Nothing he did ever made him good enough, so he might as well have fun doing it. His mother, whatever she said, was disappointed in him, because he wasn't Sirius, and he couldn't ever be her Sirius, so he didn't bother to please her in the end, because he wasn't good enough; he would never be good enough.
13. In comparison, Sirius was the outcast of his filthy rich and noble family, publically renouncing each other in turn and abandoning his inheritance without so much as batting his too long eyelashes. He was rude, he was impudent, he was daring, but he was charming, he was intelligent, and he had something of a reputation as womanizer. (He had never made the connection, but it may or may not have had anything to do with how he had never properly loved someone before, and he didn't know how to do it. There was this huge gaping hole in him that craved affection, and he used his ever changing flavours of the month to fill it, dumping them before they could abandon him.) His marks were just as perfect as his brother's, but he appeared to have put in so much less effort. He spent more time in detention than out, but McGonagall was as fond of him as Slughorn was of Regulus. To top it off, though he could never have made any position of leadership, for even Dumbledore knew better than to let him loose on the school, he was one of the most popular boys in his time, and by virtue of that, he, with his darling friends, ruled the student population, and that was that. He was always enough, more than enough, for everyone.
14. Life liked its own ironic jokes too much for comfort. Sirius, who hated his heritage and wished that he could cut his hand to bleed out his dirty, Black blood, had the steely grey eyes, wavy black hair and aristocratic features that made his terribly inbred family more attractive than most products of incest were, and, for that matter, those who weren't. Regulus, who strove too hard to be like a proper Black, had eyes too soft a blue, and too delicate were his features, to succeed. Perhaps it was a rare act of mercy, or a relief, but as they grew up, Sirius' features sharpened and there was something picturesque about his face, that made him too pretty; too wild, rubbing away the edges and lessening his resemblance to his family, and more to a little prince straight from an attica vase. Regulus' face, on the other hand, hardened as he forewent his seemingly eternal flirtation with puberty, making him more like his dour father than ever as the days went past.
15. Till each of their dying breath, they swore that they hated each other, and yet, secretly thought they loved one another. Perhaps once a upon a time, they did.