Chapter Text
Septimus
September 1st, 1937
The Sorting Hat was worthless flap of fabric that he would see burned.
‘You are Slytherin in name: Septimus Marvolo Slytherin. You expect me to sort you elsewhere? Hmph. There is no universe in which I would sort a Founder’s Heir away from their own house. No, no…’ the leather monstrosity had murmured into Septimus’s mind.
‘I am a Slytherin, yes, but I am also plenty brave and—admittedly, at times—reckless!’ he argued in return. ‘Now stop prattling on about other universes like you know a damned thing that happens outside this castle and put me with my brother!’
‘Curious… such dedication to your step-brother, your oldest friend… a trait of the Hufflepuff line…’
‘DON’T YOU DARE—I AM NOT A HUFFLEPUFF!’
‘No, indeed… you are a bit of everything it seems. Tricky, tricky…’
‘Dad said that you would listen to me!’ Septimus whined silently. ‘And Orion needs me—’
‘More than you need to accomplish your ambitions?’
‘YES!’
A beat of silence passed before the hat murmured, ‘Were you not a Founder’s Heir I would be sorely tempted to place you in Hufflepuff…’
Septimus just about ripped the rag from his head in frustration.
Honestly. What could be more ‘Gryffindor’ than sneaking through the castle on his first night at Hogwarts? He was reckless! He was brave!
(And loyal, ambitious, and smart… an annoying voice in the back of his mind supplied. It sounded awfully similar to that lump of talking leather.)
Shakespeare hummed soothingly, winding around his wrist tighter. Septimus gently—though clumsily—stroked her head in return. They were both invisible, slinking through the dark halls of the castle with only the memory of Dad’s bedtime stories as a guide to find Gryffindor Tower.
A smirk crept onto Septimus’s face at just the thought of those nightly tales. After his Hogwarts letter had arrived, it was as though a damn had broken open. Dad had begun a nightly ritual—just the two of them—in which he’d tell Septimus all about his other life. His time as a student at Hogwarts.
His time as Harry Potter.
Dad framed it to Minnie as their ‘special bonding time’ and then ensured that Minnie had her own special time each morning when Dad braided her hair. With the birth of The Trio (as Orion had taken to calling their three baby brothers), it had become a necessity for Dad to set aside time intentionally for his two eldest children. Even with the help of Woozy and Grandma Lue, Septimus hardly ever saw Dad or Arcturus without a baby in their arms or Lyra on their shoulders.
So, it was perfectly fair that Septimus had his own special time each evening with Dad.
And if that meant that Minnie didn’t get to hear Dad’s secret stories... Well. That was just the (singular) perk of being the subject of a public prophecy.
Septimus paused to catch his breath after ascending another staircase. The trek to Gryffindor Tower from the dungeons was no game of gobstones. Orion had better appreciate all the energy Septimus was putting into visiting him.
Dad had described the entrance to the dormitory many times as simply ‘the portrait of the Fat Lady,’ which was terribly uncouth as well as terribly unspecific. There were many paintings of ladies on the seventh floor near the Grand Staircase. And they came in all shapes and sizes!
But luck was apparently on Septimus’s side tonight, because just as he turned a corner, he heard a girlish giggle. There, behind the portrait of an (admittedly rotund) lady in a pink gown was the entrance to a room clearly adorned in ruby-reds and garish-golds.
A tall, older boy and plain-looking girl were loudly exiting the common room together, hands linked. The boy shushed the girl’s laughter and then checked that the hallway was empty. His eyes skated right over Septimus.
“Let’s go—I know a spot,” the boy whispered in a low voice. He tugged the girl to follow him, but she yanked him back into a messy kiss.
Septimus wrinkled his nose and shuffled his feet.
They were in his way and just so… loud.
He edged his way along the wall, face heating as he snuck past them and their gross, smacking mouths into the dormitory.
Pausing for a moment to observe the roaring fire and cushy armchairs, Septimus acknowledged that, had he been sorted into Gryffindor, he would have been stuck with a ridiculously subpar common room. Was there truly no private library? No study sanctuaries?
Even the view from the Tower windows was unremarkable; the seventh floor—open to all—supplied similar nooks to admire the castle grounds from.
Compared to the subterranean view of the Black Lake in the Slytherin common room, Gryffindor Tower was terribly pedestrian.
After (begrudgingly) admitting his good-fortune in failing to persuade the Sorting Hat, Septimus returned to the task at hand.
Finding the first year boys’ room was straightforward thanks to a prominent placard on the wall. He opened the door quietly and stepped inside, letting his eyes adjust to the dark.
Septimus had planned to identify Orion’s bed based on the location of his trunk, but that strategy proved unnecessary; he merely followed the sound of a familiar sniffle.
With a hissed spell he became visible, and with another whisper of English he announced his presence:
“Orion? It’s me.”
The sniffling stopped immediately.
After a beat, the hangings of the bed drew back. Then Septimus was unceremoniously yanked inside, eliciting an undignified squawk.
“Quiet!” Orion whispered in a crackly voice.
“You be quiet!” Septimus snapped back with annoyance. He untangled their limbs and threw an elbow at Orion. “And budge over!”
Septimus could have sworn that the next sniff he heard had an indignant undertone.
But after the petty squabbling had passed, the mood dropped again. In the dark, his vision was hardly more than a fuzzy gray-black impression of Orion’s face laying on the pillow next to him. Nonetheless, Septimus spotted it the moment that Orion’s lip began to wobble.
“I r-ruined my family’s legacy!” he choked out through sudden, heaving sobs.
“What? No!” Septimus whispered back. He instinctively pulled Orion into a hug. “Don’t be ridiculous.”
Orion’s mumbled response was mostly unintelligible, but Septimus caught on to his meaning.
“Who cares if they were all Slytherins? All of the houses have good traits. This just means you’re the bravest Black to be born in over a century.”
Though Orion’s crying quieted, he stayed silent.
“Dad told me that he and Arcturus would be proud of us no matter which house we were sorted into,” he continued.
“…He did?”
“Of course! And he was a Gryffindor, too, so he’ll be thrilled to rub this in your Father’s face.”
Orion snorted. Septimus was briefly buoyed (getting Orion to laugh was excellent progress) but then shrieked with indignation—thick snot had shot straight from Orion’s nose onto Septimus’s neck.
“Eughhh!”
He shoved Orion off the bed without thinking.
Arcturus
April 21st, 1937 (aka, ~4 months earlier)
It was rare these days to leave the manor without some combination of Harry and their numerous children.
But on the three-year anniversary of Melania’s death, he found himself at her grave in the morning dawn light. Alone.
Arcturus’s husband had a knack for making space and time for him just when he needed it. Today was one of those cases. Harry had set an early alarm—waking well before the triplets or other children would—and pulled Arcturus from bed. He handed him one piece of clothing at a time (“You need to dress for a steady drizzle,” he murmured) and kissed his brow gently. He summoned a beautiful bouquet of flowers, placed them in Arcturus’s hold, and then assured him that there was no rush to return.
He would visit once again that afternoon with Harry, Orion, and Septimus, as had become their annual, somber tradition. Lucretia, in her sixth year at Hogwarts, was unable to join them; she typically made a visit during the summer months instead.
This moment, though, was Arcturus’s alone.
“Everyone is well,” he started. “We miss you, of course.”
A beat passed with nothing but the pitter-patter of rain on his umbrella.
“Perhaps that isn’t entirely true.” Arcturus heaved a sigh. “We are mostly well, but Orion is still… well…”
He liked to imagine that, here, Melania would have chimed in to say: “Traumatized? Yes, dear, that is what happens to children forced to endure a horrific ritual—be it successful or not.”
And then she would have pointedly asked: “And what have you done to support him? To ensure his recovery?”
“He sees a Mind Healer regularly,” Arcturus offered in response to the non-existent argument. “I am not merely banishing his troubles under the rug—even I know better than that.”
“True. You are not entirely clueless with regards to child-rearing.”
“And I have Harry.”
“And you have Harry.”
Another beat passed. The one-sided conversation stalled.
“He’s scared, Mel,” Arcturus whispered, chest twisting with a strange sort of anticipatory grief. “He goes pale at the mere mention of his Heirship—at the mention of his future Lordship. He knows that Pollux targeted him because of it.”
His view of the gravestone, already rain-hazy, blurred further.
“Even I get scared sometimes, just thinking about what could have happened. I cannot remove the knowledge from my mind. That ritual—” he choked “—that combination of immutable mind magic and soul-binding contract... We would have lost him entirely, Mel. Everything that made him Orion would have been locked away forever. I cannot—” he swallowed past the lump in his throat “—I cannot imagine that I would have survived witnessing… that.”
Some days, he pictured it endlessly. That alternate world that Harry had come from—had overwritten. They once discussed how Arcturus was practically unmentioned during Harry’s youth; apparently not even noteworthy enough for Harry to recall whether he was dead or alive. The great Lord Black, reduced to a footnote…
It should have been unimaginable. And yet…
Arcturus saw that path unfurl the moment he discovered the depth of Pollux’s betrayal. He saw that divergent history in which his beautiful son was as good as murdered; in which Orion became trapped within his own puppeteered body; in which Arcturus had to live on under Pollux’s thumb, knowing that one false move could prompt further pain and torture of his child.
Arcturus would not have survived it. He would have… withered away.
It was no wonder why the Arcturus of Harry’s original timeline was as good as a ghost. No wonder why the House of Black disintegrated entirely.
“What if the Mind Healer is not enough?” he asked. “How do I help him? How, Mel?”
He failed to even imagine her response, this time. His own mind was lost; it could hardly supply the answers he so desperately sought.
“Harry thinks…” he started to say, pausing to wipe the tear tracks from his face. “Harry thinks that I should consider offering to remove the ‘burden’ of the Heirship from him.”
He imagined the way that Melania used to hum with deep thought. He imagined her response to be: “It is true that our boy was never taken by his own title.”
Arcturus smiled as a hundred memories swept his mind: Orion smiling goofily when introduced as ‘Heir Black’ to strangers. Orion looking to Lucretia anytime an important decision needed to be made. Orion playing pretend with Septimus—some game called ‘Robin Hood’—and whining when it was his turn to play the rich-noble-who-deserves-to-get-robbed.
(An idiotic game, that one.)
Orion had a knack for finding joy in every little thing. It neither mattered whether those things were big or small, nor prestigious or ordinary.
But to remove his Heirship…
“What if he regrets it?” Arcturus said with worry. “Can he really, truly understand what it means to someday become a Lord at the age of 11?”
“Did you?”
It was a challenging comparison. Arcturus had taken pride in his status as the House of Black Heir from a young age. In truth, he acted terribly towards Cygnus as a young child, quite literally lording his title over his younger brother at every turn.
“Orion… he is quite different than I was as a child.”
“Who does he remind you of, then?”
“In some ways, Harry. In other ways, no one but himself.”
The way that Harry and Orion sought joy for not only themselves, but others too, was remarkably similar. Perhaps in another life, if raised by loving parents, Harry would have been even more similar. More carefree.
“A reckless Gryffindor, then?”
Arcturus snorted. Melania never would have proposed such a ridiculous notion. His one-sided conversation had become as realistic as a Crumple-Horned Snorkack sighting.
“I miss you.”
The rain continued to beat down.
“I miss you and it is terribly, terribly unfair that you are gone. Cruel that our children had to part from you so soon. Bittersweet that when you were forced on you embraced it so beautifully. So peacefully.”
A memory—one he often returned to—rumbled in his mind:
“You promised me, Arcturus,” Melania said with a stern frown. She was propped up on two fluffy pillows, trying her best to eat the special meal that Woozy had prepared for her.
“Mel…” he grumbled.
“I only asked for one thing!” she snapped, dropping her spoon to poke him in the chest. “You said that you would accept nothing less than a love-match. You promised!”
“And I shall uphold that promise, should the opportunity arise,” Arcturus demurred.
Melania threw her arms up in the air with frustration, and Arcturus had to withhold a wince at the sight of her frail limbs. “It’s an empty promise if you never embrace the opportunity to find that love-match.”
He hummed a non-committal response.
“That kind, handsome wizard in our library—”
Arcturus attempted to cut her off with a hissed, “Mel!”
“—is everything I want for you.”
“You don’t need to—” Arcturus gestured aimlessly “—arrange for my happiness. You and I may not have been a love-match, but we have raised two children together happily, have we not?”
“We have,” Melania agreed with a subdued nod. “We made an excellent team. I am grateful of it everyday.”
Arcturus nodded his head in return, as though to say, ‘Well, there you have it.’
Melania’s pale-blue eyes narrowed. “Life is more than just raising children, though.” A faint blush rose on her cheeks, though her determined glare remained. “At least, for me it was.”
He attempted to wave the topic away, murmuring, “That was nearly a decade ago, Mel…”
“You let me stray and forgave me for it—” Melania persisted.
“You were forced to marry me by your parents,” he excused uncomfortably. “You were already in love… I could never fault you for choosing Inés over me.”
She gave a stiff nod. “I was in love, it’s true. And you were unfathomably accepting of my flightiness.” Melania huffed a sigh. “Can you not see that I want to repay you?”
Arcturus frowned.
“I treasure what I had with Inés… differently than I treasure our children—our home. They cannot be ranked or compared. The all-encompassing love I felt for her was so different, Arcturus.” Her gaze softened. “You, of everyone I have ever known, deserve to feel that kind of love most. To share it with another.”
He stood, discomfort moving his body before his mind even fully decided to flee the conversation.
“Arcturus!”
He stopped in the doorway, half-turning to listen.
“Be selfish,” she entreated. “Please. For once, put what you want first.”
“Did I exceed your expectations?” he asked the tombstone with a melancholy chuckle. “I remarried less than a year after you passed. Putain de merde—!” he exclaimed, “I fully merged my soul with the love of my life not even a year after the marriage.” He closed his eyes, breathing deeply. “I think that you would be satisfied.”
“It is everything that I wanted for you, and more.”
Arcturus knelt, placing the flowers that Harry had arranged below his late wife’s name. He brushed a finger along one of the rain-dampened petals. A white lily. The velvet-soft edge dipped under the pressure of his touch, then bounced back.
“I wish you were here, Mel.”
The rain continued.
“I wish you could tell me what to do.”
Septimus
Soon after the Snot-cident
“With loyalty like that, I am surprised the Sorting Hat did not place you in Hufflepuff.”
Septimus glared at the way Professor Dumbledore’s blue eyes twinkled. Was the older wizard teasing him? Septimus had just recounted the evening’s events, but he had intentionally omitted his argument with the Sorting Hat.
(No one needed to know about that blasted fold of fabric’s ridiculous opinion.)
But it was as though the poorly-dressed professor had somehow known. He looked far too mirthful.
“Loyalty is a… kind way to frame Septimus’s misbehavior,” Dad said with a forced smile. “I am certain that he will follow Hogwart’s curfew rules from now on—that this was just an anomaly—isn’t that right, Septimus?”
Septimus donned his most angelic smile before responding, “Of course.”
Dad’s eyes narrowed ever so slightly, making the dark circles beneath even more pronounced.
‘As if you didn’t break curfew a thousand times,’ Septimus sassed back at him, sending the thought straight into his mind while maintaining an innocent expression.
To his credit, Dad hardly reacted to the unexpected Legilimency. A small flare of his nostrils was the only cue that he’d received Septimus’s message.
‘I never woke up an entire dormroom and then had my parents floo-called-in on the first night of term!’
Septimus scoffed internally. ’You told me that you flew a car into the Whomping Willow in your second year—on the first day of term! The only reason this didn’t happen to you is because your guardians were muggles!’
The sound of Arcturus clearing his throat interrupted their silent argument.
“Well, it is quite late—” Arcturus said pointedly, moving to stand.
“Can Septimus… stay?”
The eyes of every adult in the strange, midnight parent-teacher conference swiveled to Orion. His own eyes were cast downward.
“I am afraid not, Mr. Black,” Professor Dumbledore said, voice (condescendingly) gentle. “Though the transition may be challenging, it is important that you each develop independence. Now is the time to build new connections with the students in your respective houses.”
“Oh... okay—” Orion started to respond just as Septimus blurted, “But that’s stupid!”
Dad mumbled something under his breath at the same time that Arcturus made an odd coughing sound.
Professor Dumbledore merely raised a brow at the outburst. “Would you care to elaborate on your reasoning, Mr. Slytherin?”
“Happily,” Septimus said, straightening in his seat. “Professor Dumbledore, I will see my housemates plenty—every meal, every class—it’s not as though we can even do any bonding while unconscious!” Septimus groused. “And Orion—”
Orion’s bright silver eyes, rimmed with red, suddenly rose to meet Septimus’s gaze.
‘Don’t,’ he pleaded silently, knowing that Septimus would lift the message directly from his mind. ‘Please don’t tell them.’
Septimus snapped his mouth shut.
“What about Orion?” Dad prompted with a frown.
“Er… nothing. Nevermind,” Septimus mumbled.
Arcturus and Dad exchanged a look.
“Perhaps,” said Professor Dumbledore, “Tom could escort Mr. Slytherin back to the dungeons while we finish our discussion? It is, indeed, getting quite late.”
Septimus opened his mouth to argue, but fell silent when Dad shot him a look.
:: Shakespeare, :: Septimus hissed softly. :: Would you please stay with Orion tonight? ::
:: Of course, Young Poet, :: the mooncoil serpent responded with a gentle hum.
The effect was immediate: Orion’s shoulders visibly dropped as soon as Septimus handed over Shakespeare with a whispered, “Here. She’ll stay with you tonight.”
As he left Professor Dumbledore’s office, Dad’s hand on his shoulder, he looked back briefly. Despite the professor’s excuse of the late hour, neither of the adults were readying to leave.
The last thing he saw was Arcturus wrapping his arms tightly around Orion.
Harry
He silently debated how to handle the situation, thoughts churning during the entire trek down to the dungeons. And yet, when they reached the entrance to the Slytherin common room (a nondescript expanse of stone wall) he was no closer to an answer.
“Dad?”
Septimus was shifting awkwardly from one foot to the other. His fingers played with the hem of his pajamas.
Harry gave him an encouraging smile. “Yes?”
Septimus’s deep garnet eyes looked down guiltily. “Orion doesn’t want me to tell you, but…”
“He’s still having nightmares,” Harry finished for him.
Septimus’s eyes widened. “You know?”
With a sigh, he pulled his eldest son into a tight embrace. “Yeah. We’ve known for a while.”
“Oh.”
A beat passed before Harry broke the silence. “You’re an incredible brother—and friend—you know.”
Septimus squirmed a bit, mumbling something unintelligible.
“But…” Harry continued gently, “I want to make sure that you know it isn’t your job to make sure Orion gets better.”
A beat passed with no response.
“Septimus? Do you understand?”
“Sure.”
Harry rolled his eyes. That response almost certainly translated to: I understand that you think that, but you are incorrect.
“It isn’t your job to fix everything, Moose,” he repeated with a sigh. “You’re just a kid. A brilliant kid, but a kid nonetheless.”
Septimus didn’t respond.
Septimus
He couldn’t sleep—Dad’s words kept cycling through his mind:
“It isn’t your job to fix everything, Moose.”
Of course it wasn’t his job. But that didn’t mean it didn’t need to be done, did it? This was Orion they were talking about!
And the notion that Septimus was in the habit of trying to ‘fix things’ for everyone else was, quite frankly, overblown. He was just a good friend. A good brother. A good son. He took care of what was his.
“You’re just a kid. A brilliant kid, but a kid nonetheless.”
His physical age was hardly relevant. Dad spoke as though Septimus was too young to bear burdens—and it irked him.
Septimus had borne the burden of the prophecy, hadn’t he? For over three years now, he had demonstrated how resilient he was.
But in Dad’s eyes, he was still a fragile child.
He flipped onto his side with a huff. There was a soothing, hazy green light that drifted into the dormitory from the dark lake-view windows. It cast the room in murky shadows. Were he to need to navigate in the night, he could likely do so with little difficulty.
Septimus’s eyes drifted, inevitably, to his nightstand. On it were three letters, retrieved from the bottom of his trunk just before crawling into bed. They were all old birthday correspondences. They were all addressed to Heir Slytherin.
They were all from the same wizard.
The first letter had arrived on December 31st, 1934:
Dear Heir Slytherin,
Though many may speculate otherwise, I mean you no ill will. On the contrary, I do indeed hope to someday meet the most powerful wielder of the new age. For I do not draw hasty conclusions, and the prophecy indicates neither conflict nor opposition between us.
I openly admit to my curiosity: What shall you wake from dormancy? What shall set you on the path to meet me? What might we accomplish together?
I expect that time will tell.
Many happy returns on your ninth birthday.
Yours sincerely,
Gellert Grindelwald
It was miraculous that Dad hadn’t spotted that first missive—lucky that he had been particularly distracted that year; he and Arcturus had just returned from their honeymoon, after all. The morning after Septimus’s birthday, he handed over a stack of birthday post—unchecked—almost mindlessly.
The second letter had arrived on December 31st, 1935:
Dear Heir Slytherin,
Another year older, another year wiser.
Another year closer to when you shall join me, I dare to hope.
Many happy returns on your tenth birthday.
Yours sincerely,
Gellert Grindelwald
And the third letter had arrived approximately nine months ago, on December 31st, 1936:
Dear Heir Slytherin,
Have you seen? Just last week, the Polish Ministry for Magic declared it:
“Grindelwald becomes Conqueror of the West!”
Worry not, I shall remain as such indefinitely. I know that you shall rise to meet me, to join me, in time. You still have much to learn before that day comes. Many years of schooling to complete.
Perhaps, after your schooling, we shall extend my territory past the continent together. After all, Britain is your home, and your birthright.
Many happy returns on your eleventh birthday.
Yours sincerely,
Gellert Grindelwald
He had never shown the letters to Dad (nor anyone else, for that matter). Septimus knew that his family worried for him. Worried about the prophecy. There was simply no reason to cause them any further strife.
They were happier, not knowing.
“It isn’t your job to fix everything, Moose.”
Dad’s voice echoed in his mind. He would want to know about the letters. Septimus knew that he would want to know.
“You’re just a kid.”
Should he tell him? Was there any point? What if it just caused him needless worry?
And what if they had interpreted the prophecy wrong?
The prophecy indicates neither conflict nor opposition between us.
What if… Grindelwald meant him no harm, after all?