When he was born, he was like a miniature of his older brother, and everyone said that they could be twins, and he was the perfect spare to the family.
Unfortunately, by the time he was six, they realized that he was nothing like his brother. Whilst Sirius burned with the hidden family fire, Regulus was quiet and still. Sirius, like Bellatrix, was movement, like fire that wavered and swelled and burned so bright. Regulus was cold and still, like water.
It was hard to be still around the two of them. Often, he felt left out, sitting quietly at the side, all but forgotten.
It was at thirteen when Bellatrix first noticed him. She was seventeen, in her last year, and hardly different from when she was seven and set fire to one of their numerous relatives. It was at one of those useless family gatherings when she noticed him crouched in the shadows, staring blankly at the glittering lights. Sitting next to him, she gave him that achingly familiar grin, mad and reckless. (He pretended he couldn’t see the edge of cruelty in her eyes when she kissed him.)
For once, someone had actually bothered to notice him, and he felt so alive, as her wild momentum carried him along, and he pretended that she wasn’t carrying him over the edge of the cliff.