Growing up as the only daughter of the noble and most ancient house of Black, you determined early on in life that you were never destined for happiness. That was bearable, however, because you had your brothers. They were your only solace. One, your protector, the other, your platonic other-half.
Nevertheless, as time passed, those same consoling figures grew apart and a once unintelligible rift in their bond had become a crumbling tower that all but collapsed before you even reached 15 years old.
Sirius had run away and left you and Regulus in the house that wasn’t a home to any of you. You couldn’t blame him; if you had the same courage, you would have done the same. That was the only comforting thought you could muster to quell the bitter ache sprouting from the flagrant, indisputable fact that Sirius had practically abandoned you and your twin brother.
From there, you and Regulus had become one another’s comfort, the pillar both of you knew you could rely on when close to your own collapse, whether emotional or physical. You treated his wounds, he treated yours and as twins, you never could have been closer.
There was a noticeable acrid flame alight in Regulus however, that pushed Sirius further and further away while you remained unemotional over the ordeal. Your twin was rightfully hurt by the one figure he had always looked up to and you needed to be the neutral calm to his torrential storm of acrimonious sorrow. He was silent about it, speaking through his actions and rebellion against Sirius through the conforming of your parents’ ideals. They were overwhelmingly proud when he took the mark but you worried inexhaustibly; you knew that if Regulus had a choice he wouldn’t have chosen such a path and you knew that if Sirius was still here then maybe…
You steeled yourself and leaned into your twin brother’s back, your forehead between his shoulder blades as your arms wrapped around his waist. He grew to be a silent man who spoke through actions rather than words and so you had built this silent habit to comfort him wordlessly. All Regulus needed was to feel that someone, someone tangible and who was right beside him was always going to be there despite being out of sight. He appreciated your actions deeply.
Sirius, caught up in the distractions of his friendship, neglected to see the flat coldness that consumed your mannerisms, your silhouette and once bright eyes. Gone was his sweet sister who sought comfort in him, instead you stand on your own, strong but terribly alone. He had also failed to acknowledge the deep hurt reflecting in his only brother’s eyes. They plead him to notice, to look his way and miss the past, to, somehow, rekindle a past bond that was so strong it won against all that stood before it. But it never came. Sirius never once looked and a cold steel metal accumulated in Regulus’s bones. There was no point.
But that wasn’t true. Sirius did look. And he did notice. But something held him back, perhaps it was his own cowardice, maybe it was because he was still taking the time to come to terms with the fact that things were never going to be the same or maybe it was because of the shame he felt for having abandoned his younger siblings. He knew you and James exchanged brief letters concerning his condition, his happiness and wellbeing but those letters were quickly dwindling in frequency - Sirius couldn’t conclude whether he should feel relieved or saddened by that.
It wasn’t until Regulus disappeared without a trace that Sirius felt a jolt inside him, pushing him forward regardless of any lingering emotions. However, he was delayed by the actions of war and soon was left in hysterics over your successive disappearance as well.
Sirius couldn’t collect himself enough before he was barging back into 12 Grimmauld Place to confront the woman who, not only succeeded her husband, but her two youngest children as well. He demanded answers, his throat sore from the shouting and tears he shed.
The only answer he was able to grasp was that after Regulus mysteriously disappeared and presumed dead, you had grown anxious and paranoid, determined to investigate his inexplicable death. You had raided Regulus’s room for answers and with your investigations and, perhaps even your bond as a twin, you followed what little traces Regulus had left behind.
“She wouldn’t take no for an answer,” Walburga spat, “so she got herself killed too,” there was a visible lining of tears in her eyes - the nerve, “now I have to bury two empty caskets,”