The Son of the Stars

⭑

The sunlight shone through the branches of the trees above as Regulus ran through the woods, casting a green glow over the forest floor. On another day, during one of his regular walks in the woods, he might’ve stopped to appreciate the effect, looked up to let the light warm his face. Now, though, Regulus couldn’t think about anything except what he had left behind in Cabin Eleven, stalking out of the cabin without a word and before anyone could stop him. As far as he knew, Sirius hadn’t tried to follow him. Typical.

He broke through the trees into his clearing, a small glade surrounded by tall maples and oaks. Regulus had found it on one of his first weeks at Camp Half-Blood, escaping to the woods when he couldn’t deal with the stares and the whispers. He knew being a child of Hades, likely the child of the prophecy, came with a certain notoriety, but it wasn’t something he asked for. So he came to the woods as much as possible.

He started speaking to the trees, because he knew they didn’t care who his father was or where he came from. They never judged him or expected anything from him. So he told them his story. His childhood, his parents, his brother. Regulus’ constant work to meet his parents’ impossible expectations. Sirius leaving Regulus alone in that house. How everything got worse afterwards, how the pressure got stronger, how he had to work harder, even when nothing about his responsibilities came naturally to him. 

How Regulus had left for good at the end of last summer. A gryphon had caught his scent quickly and had followed him for miles, and Regulus kept it at bay with the single knife he had brought from his parents’ home. He had finally run across a Camp Half-Blood patrol, consisting of two boys Regulus would soon come to know as Evan Rosier and Barty Crouch, who helped him take down the monster and led him to camp. 

Regulus’ first few hours spent at Camp Half-Blood were blissfully peaceful. He learned that there was a place for him, that everything about himself that he had tried to suppress for so long to appease Orion and Walburga was normal, even celebrated. He could stay here as long as he wanted, and he could never be reached by anyone from the outside world. He would find a real family in his cabin, when he was claimed. He had another chance at having a parent, at having brothers and sisters.

And then a glowing sceptre appeared above his head in the middle of the mess hall. A symbol none of the campers had ever seen, and Regulus was quickly ushered to the Big House. An ashen-faced Chiron explained to him that he was a child of Hades, a child that shouldn’t exist. He didn’t actually fit in anywhere in camp. He didn’t have a place to belong. And on top of that, he was most likely the subject of a prophecy that caused the Big Three gods to stop having children in the first place, and wasn’t even allowed to hear the actual prophecy that might determine his fate and his future.

So Regulus didn’t feel much like speaking to human beings for a while after that.

Pandora had revealed herself shortly after Regulus found the glade. Apparently, the whole time Regulus thought no one was listening to his stories, the dryad that embodied the clearing’s weeping willow tree had heard everything. Regulus almost pulled away, almost gave up what he thought was one of the only safe places he’d ever found. But Pandora still listened the same way she always had, allowing Regulus to get everything off his chest. She never offered judgment and barely ever gave advice, which Regulus appreciated. Most of the time, he just wanted to be heard. 

As Regulus approached this time, she was sitting at the base of her willow, her green dress blending into the mossy earth and her long golden hair the same shade as the drooping fronds. She sat up, clearly surprised at her visitor. “Regulus, is everything okay? I wasn’t expecting you to–”

“My brother is here,” Regulus cut her off. “At camp. In my cabin. He’s a half-blood. He’s here.”

Pandora barely ever lost her composure, but Regulus saw her eyes widen as she took in his words. “Sirius?”

Regulus flinched imperceptibly at the sound of his brother’s name. He had heard it aloud so few times in the past four years, and yet every mention of it made Regulus’ jaw clench. 

When Sirius had walked into the room, Regulus was sitting on his bunk playing cards with Evan. They had heard they were expecting a new camper, but all Regulus knew was that he was unclaimed and had killed a monster close to the border of camp. He didn’t really bat an eye at anyone joining the Hermes cabin. Campers rotated in and out so often that Regulus usually resolved only to pay attention to them when they remained unclaimed, when Regulus knew they were sticking around. So he wasn’t expecting much when he glanced at the door, only to sit straight up, chest tight, trying to force himself to breathe. 

Regulus didn’t want to think about all this meant. Was Sirius another son of Hades? And if not, who was his godly parent? What role did their parents play in all of this? Regulus had believed he had escaped them when he left home, leaving them and all of their complications behind. Even when he was claimed, he could take comfort in the fact that he would never again have to deal with the troubles of having a family. He was alone, and he could make his own way in the world.

Maybe, Regulus desperately thought, Sirius would just leave him alone. Maybe he could accept that their relationship was beyond repair. Sirius would find his own family soon enough, when he was inevitably claimed and left Regulus again.  There was a chance they weren’t even actually biologically related, if Sirius’ godly parent was his mother. He probably wouldn’t want to have anything to do with Regulus anyway. Good. It was for the best.

“Did he say anything to you?” Pandora asked as Regulus sat beside her on one of the willow’s roots, leaning against its trunk. 

Regulus shook his head. “I ran out before he had the chance.”

“And what do you want to do?” Pandora leaned her head on Regulus’ shoulder, and he barely had to resist the instinct to pull away. Regulus had always had trouble with physical contact. Pandora was a rare exception. She somehow always knew when Regulus could be touched, when he was upset but not overstimulated, when the comfort of someone else wouldn’t make him feel like his skin was too tight for his body, or make his throat close up. Having her close to him felt like a cool breeze rustling through leaves. It felt like she was taking a deep breath for him. 

“I don’t want to talk to him,” Regulus confessed. “I want to stay as far away from him as possible.”

“That’s okay,” Pandora mused.

“But how can I when he’s going to be sleeping ten feet away from me?” Regulus exclaimed. “I can’t go back there. Not while he’s around.”

“Well, you have to sleep somewhere,” Pandora pointed out.

“I could leave,” Regulus said. “I can take care of myself. I could last a while on my own, at least until the summer ends.”

“And what if he stays longer?” Pandora asked. “Or tries to follow you?”

“Don’t worry,” Regulus said bluntly. “I don’t think he wants anything to do with me.”

Pandora considered this, but didn’t object. “All I know is that you can’t run away from your problems. That doesn’t mean you have to speak to him, or interact with him at all, but you shouldn’t be forced to leave just because he’s here. This is the safest place for you to be. You can’t be running into danger in order to avoid your past.”

“You’re right,” Regulus replied resolutely. “He needs to leave.”

Pandora smiled. “That isn’t quite what I meant. Camp is the safest place for him too, you know.” 

“I don’t care,” Regulus said, hoping the stubbornness in his voice masked the uncertainty of his words. “I was perfectly fine before this. I had my life back. And now he’s back, and he’s ruined any chance I ever had at moving on. He should be the one to go.”

“Unfortunately, I’m not sure that’s up to you,” Pandora said. 

Regulus leaned his head towards her, so his cheek was touching her hair. “I hate him,” he confessed. His throat felt thick. “He ruined my life. He left me alone. I barely made it out of there, and he just abandoned me without a second thought. And seeing him again felt like four years of anger and resentment is right at the surface, and it’s all been waiting for him.”

“You’re allowed to be angry,” Pandora told him. “Your reactions are perfectly justified. Anyone else would feel the same way if they were in your shoes.”

“But I don’t know if I can control myself,” Regulus said. “It’s not just that I feel angry. I want to hurt him. I want him to feel the way I felt. And I don’t know if I can be around him without doing just that.”

Pandora took her head off his shoulder to properly face him. “You’re stronger than you think, Regulus. The gods have never made their heroes’ journeys easy. You’ve overcome so much to get here, and you will overcome this too.”

And really, Regulus had nothing to say to that. Pandora had a way of saying things like that, making them seem to matter-of-fact, like they must be true and anyone who doubted it was entirely unreasonable. It was almost enough to make Regulus believe it too.

The two of them stayed like that, seated at the base of Pandora’s willow tree, until the green glow between the leaves faded as the sun dipped below the horizon. 

☼

James knew from a very young age that no one wanted to see anyone else’s ugly feelings. The “problem children” were those who cried or threw tantrums, while James’ parents were always told what a pleasure he was to have in class. And it felt so good being good, that when he skinned his knee playing tag or the older kids made fun of his glasses, he simply pushed the pain away. He would always try to befriend those children who were easily upset. Ignoring something that hurt was second nature to him, so how hard could it be to teach someone else to do it?

James knew that was one reason why he and Sirius became friends. Even when they first met, he knew Sirius was in pain. Not in the way that James was when he skinned his knee, all but forgotten after his mother had kissed it better, but constant, internal misery. James knew that some days he was the only thing that made Sirius truly smile. So he made it his mission to be the bright spot in Sirius’ day. He made joke after joke, he told ridiculous stories, he invited Sirius to come home with him any opportunity he got. In turn, Sirius opened up to him, letting him inside, telling him the truth of what went on behind the closed doors of the Black family home. 

Of course, this only made James double down on his efforts to make Sirius feel better. He never wanted to show Sirius how his stories made him feel, because he would never allow Sirius to feel like a burden, so he showered him with cheer and light instead. And in the process, James pushed his own heartache deep inside, only resurfacing when he was alone. Only then could James feel the extent of the rage he felt toward Sirius’ family, screaming into his pillow, wishing horrible things on everyone else living in that house. Only then, when no one else was watching, could he let his tears flow, because what right did he really have to cry?

Now, on a day when James’ worst nightmare had come true, when nothing felt right anymore, when he could barely bring himself to stand up straight, he was sitting on the porch of the Apollo cabin with his best friend’s head buried in his chest, stroking his hair and promising him that everything would be all right. Because Sirius had just seen Regulus again.

James hadn’t processed the loss of his parents for a long time after Sirius had told him, because it didn’t feel like it could possibly be real. James had seen them just hours earlier, kissing them goodbye at the train station and promising to write letters that now he would never send. Obviously they had just settled in from the long trip back home. Monty was frying eggs on the stove while Effie did the crossword. He would send them an Iris-message in a couple days to check in on them, and tell them all about how Sirius was settling in. Right?

He felt like some greater force took control of his body, forcing his limbs to keep moving as he told Sirius about camp. His mind felt like it was stuck on a loop, reminding him of the unspeakable truth and then refusing to believe it in the next moment. James’ brain was a natural at suppressing negative feelings, so for short moments he could actually forget. Laugh at a joke, smile at his friend. And then it all came rushing back, almost driving James to his knees. His parents were gone. 

But if there was ever a time James needed to be strong for Sirius, it was now. He had just been attacked by two monsters, witnessed the death of the closest thing to parents he had ever had, found out that he was a demigod, and now been confronted with his little brother. So James swallowed his agony, his fury, and his dread, filing them away next to all of his other ugly feelings. 

James had often seen Regulus in passing when they were children. They had all gone to the same school until James and Sirius were eleven, but Sirius generally avoided him in the hallways, more so as they both grew older. James remembered how Regulus used to follow them around on the playground, his round face falling and giant blue eyes watching dolefully as Sirius pulled James away. His pursuits eventually evolved into glances from afar, which in turn faded away. 

The boy James had seen in the back corner of the Hermes cabin was almost unrecognizable. His face was no longer round, but angular and sharp instead. He was a couple of inches shorter than Sirius, with slightly broader shoulders and a stronger frame. His hair was shorter than Sirius’, too, and curled around his face in dark tendrils. But his eyes were the same icy blue that James had seen on that playground, the same blue as his brother, and filled with the same sorrow. 

“How can he be here?” Sirius was saying. He didn’t have tears in his eyes, which wasn’t all that surprising to James. He rarely saw Sirius cry. Usually when he was upset, he either got very quiet and withdrawn, or defaulted to anger. Right now, Sirius seemed to be feeling the latter. His hands were trembling in his lap, and James could see crescent-shaped grooves where his nails had dug into his palms. 

“I don’t know,” James said gently. He reached out for Sirius’ hands, steadying them in his grip. “I don’t know.”

“It doesn’t make any sense,” Sirius went on, barely registering James’ touch. “You said most gods don’t have children with the same mortal twice. Why would any god be fucked in the head enough to have two children with my mother?”

“We don’t know for sure that’s what happened,” James said, trying to force a calming air into his voice. “Hades might not be your parent.”

“So you think she was actually able to pull two Olympian gods?” Sirius retorted incredulously. “Or even less believable, gods slept with both of my parents?”

“You can’t know anything until you’re claimed,” James said. “I’ve never met anyone here with a demigod sibling. I have no idea how this kind of thing works. We could talk to Chiron, see if he has any experience–”

“No,” Sirius interrupted, shaking his head. “If Chiron knows, then the whole camp will know, and then we become a problem that needs to be solved, something that everyone needs to have an opinion about, and I can’t–” He took a deep, shuddering breath. “I won’t be able to do this if everyone’s watching us.”

James nodded.

Sirius sighed, seeming to deflate as the tense anger left his body. “I never wanted this,” he said helplessly. “I want to go back to how things were.”

James’ heart clenched, because oh, how he would give anything to take Sirius from here and never return, if that meant they could go home to Effie and Monty. But all he could say was “We can’t. Everything is different now. There’s no going back.”

“We had it good, didn’t we?” Sirius looked so small, the defiant flame from just moments ago nowhere to be found. “Everything was so good. And I ruined it. I ruined everything.”

James tried to respond, to say No, you didn’t. You couldn’t have done anything to save them. This isn’t your fault. And he knew that was true. But there was a tiny, horrible, evil part of him that kept his mouth closed. A part of him that was so, so angry. That didn’t care that Sirius was his best friend, and was hurting just as badly as he was right now. An irrational part of him hating Sirius for what he did. 

Sirius seemed to understand James’ silence, his face crumpling. “I’m so sorry,” he breathed at barely a whisper. And somehow, the utter helplessness in his voice broke through James’ grief in a way nothing else had.

“Hey, look at me, okay?” he urged Sirius, taking his face in his hands. His best friend met his eyes, both pairs glistening. “There’s no going back. Neither of us can keep being overwhelmed by the past, because there is way too much going on in the present. And we will face that, and get through it, and get back to that good place again. Together.”

Sirius nodded silently, and wrapped his arms around James’ neck. James’ arms encircled Sirius’ waist in response. 

They stayed like that for a long time, each one holding the other.

⭑

Regulus stared down at his dinner, pushing his chicken around the plate with his fork. He was determinedly not looking at the table that held most of the Apollo cabin, where Sirius was sitting. He had a feeling that his brother was glancing over at him every once in a while, and if Regulus caught his gaze, he wasn’t exactly sure how either of them would react.

Evan and Barty placed their plates on either side of Regulus, taking their seats beside him. Barty’s was piled about a foot high with what looked like every dish the buffet table had to offer, which he immediately dug his fork into. Evan, on the other hand, saw the look on Regulus’ face and immediately glanced across the room. His mouth twisted into a frown, and he shifted closer to Regulus on the bench. “He’s looking over here again,” he growled. 

Regulus only shrugged in response.

“Do you want me to do something about it?” Evan continued. “I don’t have a problem going over there and telling him to eat shit.”

“No,” Regulus insisted. “I’m not going to give him the satisfaction of any of us responding to him. He won’t get a reaction out of me.”

“Fine.” Evan couldn’t resist sending a heated glare in Sirius’ direction before focusing back on his dinner. “But if he ever tries to bother you, I’m not sure I’ll be able to stop myself.”

“Please don’t,” Regulus said, but he couldn’t help cracking a small smile. “I don’t want to make things worse than they already are. Plus, I don’t want you defending my honor. It makes me seem like I care, but I’m too scared to do anything about it.”

“What if I only do it if he tries to bother me?” Evan countered. “Then it wouldn’t even be about you. It would just be that he’s the worst and I hate him.”

Regulus snorted. “Well, there isn’t much I can do about that, is there?” 

“There really isn’t,” Evan grinned.

“Ooh us ee a ish ashun,” Barty helpfully added, his mouth full of mashed potatoes.

“Excuse me?” Regulus raised an eyebrow.

Barty rolled his eyes, and made a show of swallowing his mouthful of food as the other two boys waited. “You just need a distraction,” he enunciated. “Your chance might be coming sooner than you think. I heard from Dorcas that Chiron was talking about a potential quest coming up. You get on that, you’re away from him for a good long while.”

“A quest?” Evan leaned forward. “Really?”

Barty nodded. “Apparently something was stolen from Olympus last winter. Dorcas didn’t know what it was, but Chiron said that the gods are angry and want some of us to track it down. Because gods forbid they deal with their own problems.”

Thunder cracked in response, but the only reaction it got from the three of them was an eye-roll from Evan. Regulus was used to his friends’ tirades about the gods, but none of them were scared of retaliation. The truth was, as children of minor gods, the Olympians didn’t care enough about their opinions to punish them for their supposed insubordination. Regulus probably had the most at risk as a child of Hades; the gods already weren’t huge fans of the fact that he existed. So he made the fewest comments about his feelings on the gods, especially in public, but he wasn’t afraid to show his agreement with Barty and Evan’s comments about the Olympians.

Barty had been claimed after his first few weeks at camp. It was rare for a minor god to claim their demigod child in the first place, and Barty was one of the first at Camp Half-Blood. Ultimately, though, the two torches that had appeared above his head symbolizing the goddess of magic, Hecate, had not affected his life much at camp. He had gone back to his bunk in the Hermes cabin, and woken up to a conversation with Chiron where he was told there were no plans for that to change. 

Evan was never officially claimed, but even before he came to camp, he’d had vivid dreams about his godly mother. Hebe, goddess of youth, had appeared to him in his sleep several times throughout his life, showing him who he was and eventually helping him find his way to camp. Ironically, Evan had one of the most attentive relationships with his godly parent of all of the campers. Hebe had no intention of claiming him, which Evan didn’t protest. They both knew it wouldn’t make any difference.

Regulus had bonded with Evan and Barty because they all had that in common– knowing there was no one else like them at Camp Half-Blood. They were forced to find their own community. They shared the same cynicism of the rest of camp’s celebration of the Olympians, and they didn’t especially care who knew how they felt, not even whichever Olympians had nothing better to do than to listen to the dinnertime conversation of three teenagers.

“You could easily get Chiron to assign you to the quest,” Barty continued, spearing a green bean on his fork. “He’s been wanting you to prove yourself to the gods for ages. After all, you are the subject of the prophecy.” The sarcastic dramatism he placed on the last word made Regulus elbow him in the side.

“And there’s no way Chiron would have a new camper assigned directly to a quest,” Evan mused. “That might actually be a good plan.”

“You don’t have to be afraid to call me a genius, Rosier,” Barty quipped.

“I don’t think I ever need to be afraid of saying that.”

Barty made a face at Evan, flicking his fork at him. His green bean went flying and hit Evan square in the forehead, falling into his lap. Evan gasped, bringing his hand to his face and staring wide-eyed at Barty, before balling up his napkin and throwing it across the table at the other boy. 

Regulus simply leaned forward, allowing the others’ back-and-forth to continue behind his back. He was used to Barty and Evan’s scuffles and tuned them out, thinking about the idea of going on a quest. It really wouldn’t be the worst thing in the world, would it? He didn’t feel especially strongly about helping whatever god had lost their favorite sword or pair of shoes or whatever, but it would give him a chance to get some space from camp. He wondered who would be allowed to come with him. Barty and Evan would obviously be the best-case scenario, but Chiron likely would take issue with three members of the same cabin taking on a quest, despite the fact that none of them were actual children of Hermes. 

Regulus’ thoughts were interrupted by Severus sitting down across from the three of them. Barty and Evan’s brawl subsided as they registered his presence, turning back to face the table. 

“How are you doing?” Severus asked as he spread butter on a dinner roll. Regulus caught his eyes almost imperceptibly shifting to Sirius’ table. “I didn’t see where you went this afternoon.” After your brother showed up was unspoken, but they all heard it.

“Fine,” Regulus replied shortly. He didn’t really want to discuss this again. He’d had to relive it one too many times already. Severus only nodded, seeming to understand where Regulus was coming from.

It wasn’t that Regulus didn’t think he could share this with Severus. Regulus had resented him at the beginning of his time at camp, as the figurehead of the cabin he didn’t belong in and wanted so badly to escape. But over time, Regulus gained a begrudging respect for the Hermes head counselor. Severus had been at camp for eight years, watching the numbers of the Hermes cabin grow. Even though he had been claimed by an Olympian, he felt just as stuck as Regulus did, forced to watch over the largest cabin without much assistance from the camp’s leaders. Not only were the Hermes children some of the rowdiest Regulus had ever met, but the unclaimed children were unpredictable and each presented their own challenges. Severus took it all in stride, never breaking his cool facade. 

Regulus had never told him the full story of his past before arriving at camp, much like Severus hadn’t told Regulus everything. Still, as time passed, they began to understand each other. Regulus would talk a little bit about his feelings about his brother, and Severus would respond with some detail about his mother. They could see that their pasts paralleled one another, that they came from the same type of home. There was a solidarity generated from that understanding that was not easily broken. Regulus knew that this was why Severus responded the way he did when Sirius entered the Hermes cabin, his immediate hostility without hesitation. 

“Of course he’s sitting with Potter,” Severus was saying, glaring at the boy sitting next to Sirius. “I’m sure they’re very happy together.”

Regulus’ eyes widened. “That’s James Potter?”

Evan looked at him blankly. “Who else would it be?”

“I always forget that you weren’t here last summer,” Barty said. “Well, Regulus, I guess this is your introduction to the famous James Potter.”

A horrible realization was dawning on Regulus, as he brought himself to finally look over at his brother’s table. Sirius was thankfully distracted, laughing at the boy to his right, the same boy who had introduced Sirius in the Hermes cabin. Regulus had felt a nagging sense of familiarity when he saw him then, but couldn’t place where he knew him from. Now, seeing the two of them together, it hit him.

That was James from his and Sirius’ childhood, the James that Sirius always ran off with, the one that he ignored Regulus for. The boy that Sirius went on and on about for years, who became his favorite person, his confidant, his partner in crime. 

For a long time, Regulus associated the name with bitter longing. In the beginning, he had tried to spend time with them, following them around the playground, desperate for their attention. Regulus never understood what made this other boy so much better to be around, but he wanted to find out. But Sirius was always faster, running away with James in tow. Eventually, Regulus gave up, resolving to watch them from across the yard. He saw Sirius light up in James’ presence, in a way that he never did around Regulus. And beyond the overwhelming anger and jealousy, a small, treacherous part of him still wanted to be around them, to feel the way they did. He never really got to have that person, who made his life better just by being in it. The closest he ever got, for a very short time at the beginning of his life, was his older brother.

He hadn’t ever made the connection between Sirius’ James and the James he had heard about at Camp Half-Blood. His name was brought up occasionally by the year-round campers, but not in any particularly memorable way. The real reason James Potter was so familiar was Severus’ vitriolic hatred towards him. Severus never mentioned a specific reason for his problems with the other boy, so Regulus always assumed it was one of those fundamental differences between people, that they would always dislike each other despite not having a concrete reason. He sometimes thought it was funny when he had to echo Severus’ disparagement of a boy he had never even met before. It wasn’t very funny anymore. 

Regulus wasn’t sure why, but this was his tipping point. He stood up abruptly, his hip bumping into the side of the picnic table. He bit back the wince that was brought on by the blooming pain in his side. “I think I’m going to head back to the cabin.”

“Are you sure?” Barty asked. “There’s a bonfire tonight, the first one of the summer. You don’t want to miss–”

“I’m sure,” Regulus cut him off. “I’m too tired anyway.” He knew how untruthful this sounded.

Barty opened his mouth, but Severus placed a hand on his wrist, silencing him. “We’ll see you back at the cabin, Regulus.”

Regulus could only nod in response. He stalked toward the door, ignoring any looks from the tables he passed. He kept his brisk pace until he reached the Hermes cabin, where he made a beeline for his bunk. He pulled the covers open and climbed in, not bothering to change out of his clothes.

Regulus lay there as the light grew dimmer through the windows and the shadows inside lengthened. He could hear the faint sound of the campers around the bonfire. His anger grew and grew thinking about Sirius getting to experience the community of Camp Half-Blood, while he sat alone in an empty cabin. Try as he might, he could not force himself to fall asleep. 

A creak behind him signaled the door opening, making Regulus stiffen. He was facing away from the entrance, so he couldn’t tell who had come in, but he had a pretty good guess. He closed his eyes tightly and tried to breathe evenly, pretending to be asleep. 

“Regulus?”

His brother’s voice echoed in the still air. Regulus could tell that Sirius was right next to his bunk, so close he could reach out and touch him. The cloth of his pillowcase suddenly felt too rough on his cheek, almost prickly, microscopic needles scratching his face. He focused on his breath, not letting it quicken in response to Sirius’ voice. In, out. In, out. 

“Regulus, are you awake?” Sirius persisted. “Come on, it’s just us in here. We need to talk about this.”

Regulus’ hands were shaking under the covers. He clenched them into fists. In. Out.

After what felt like an age, Sirius sighed in resignation. Regulus could hear his footsteps recede, shuffling off towards his assigned bunk. The tension didn’t subside in his muscles until he stopped hearing Sirius moving around, seemingly having gotten in bed.

Even then, Regulus lay awake in the dark, unable to fall asleep, trying not to listen to his brother breathe.