A/N: I'd like to give credit to hillstar for the idea for this. Thanks so much! I hope I did it justice!

Weekly Character Appreciation Challenge: Regulus week

If You Dare Challenge: 547. Prison

The Valentine Making Station: Candy - Hug Me: Write about a sibling relationship. Misc. - Calligraphy: Write about a note.

Gringotts Wizarding Prompt Bank: Family Vocabulary Prompts - 8. Brother

Regulus Black didn't care what happened to him now. He'd been careless and stupid, letting himself get caught. What had truly been stupid had been joining the Death Eaters in the first place. He'd been promised that he would be in You-Know-Who's inner circle. But that had never happened. And now, even though he hadn't harmed a single person during his time as a Death Eater, his mere association with that group had him in some serious trouble. The Ministry was far too eager to lock people up right now. He'd be lucky to get off without at least several years in Azkaban.

Gazing around at the faces before him, Regulus didn't see anyone from his family. His parents, who had been so pleased when he'd joined the Death Eaters, had gone silent concerning their youngest son after he was apprehended. As for his older brother Sirius, he hadn't expected to find him among this crowd. While he might've been pleased with Regulus's current situation, he would never have bothered to show his face.

Regulus didn't even react when his sentence was given – a lifetime in Azkaban. His life had been one bad turn after another. Why should he be surprised that things were just getting worse?

Regulus had lost track of the days. It felt like he'd been here, rotting away in Azkaban, his entire life already. He had heard that men went mad within weeks of arriving, and now he understood why. The dementors guarding the place sucked all of the happiness out of a person. He had known this before, but actually experiencing it was a completely different matter. Every happy thought or feeling of hope fed the dementors and pulled him farther into a pit of despair and depression he had no chance of getting away from.

Day after day, week after week, he relived every bad thing that had ever happened to him. Being betrayed by his parents when he needed them the most. All of the cruel and hateful things his brother had said and done to him over the years, a betrayal in its own right, as his brother had protected him when they were younger. The knowledge that he had never had a true friend in his life, had only been surrounded by people who admired and respected his pureblood status and family name.

Regulus refused to give in to the madness threatening to take over his mind. He heard the screams of the other prisoners in their various stages of insanity. Several times a week he heard about prisoners who had finally died under the strain of their environment. He refused to end up that way. There were days when he thought it might be better to die, just fall asleep and never wake up, but some stubborn part of him wouldn't allow such a thing. He sometimes blocked out everything happening around him, a defense against losing his mind completely.

Since each day blended into the next, Regulus wasn't sure when the new prisoner had arrived. It seemed that the Aurors were busy as there were new arrivals nearly every week, but this one seemed different. The dim light in the prison didn't allow Regulus to get a good look at the man, who had been placed in the cell across from him, but there was something about him that seemed familiar to Regulus.

Regulus watched as the new arrival paced back and forth in his cell for the first few days, refusing to eat and barely sleeping, at least as far as Regulus could tell. Sometimes he would sink to the ground and start sobbing. When he did sleep, he usually cried out to someone, begging them to forgive him. Whatever had happened to this man in his life, it hadn't been pretty. Regulus tried not to get used to his presence. He'd probably either be dead or insane within a month.

Regulus was awoken one morning by a strange sound. Fighting through the fog of sleep, he focused on the sound and realized it was a voice. Someone was speaking. Not entirely unusual, but this voice didn't sound crazed and on the edge of despair, which was all he usually heard these days. He sat up and looked around, his gaze falling on the cell across from him. The new man leaned casually against the bars, arms crossed, appraising Regulus in a strangely familiar way.

"Finally decided to pay attention to me?" the man said, sounding just as calm as he looked. "I've only been trying to wake you for hours. Well, at least I think it's been hours." He turned his head and looked up at the small barred window in his cell. "Hard to tell in this place."

Regulus was amazed. This was probably the only prisoner in Azkaban who could speak in such a calm and casual way. "What are you?" Regulus croaked out.

The man laughed, a barking sort of laugh. The sound of laughter seemed so foreign to Regulus that he jumped. "No, really," he persisted. "You must be the sanest man here. You can't be human."

"Says the only person I've heard utter anything coherent since I got here." The man chuckled. "I have my ways of fending off the madness. What about you? How are you keeping your wits about you?"

Regulus shrugged. "I just refuse to lose myself to this place. Something in me is still holding on."

"Well, you'd best keep holding on," the man replied. "I need someone to keep me entertained for the rest of my miserable life." He lowered himself to the ground, wrapping a hand around one of the bars. "What's your name?"

"Regulus. Regulus Black."

Regulus heard a sharp intake of breath. Like maybe this stranger wasn't a stranger at all. He had the nagging feeling he'd met this man before. "Do you recognize my name?"

"No," came his companion's terse reply. "Never heard of you."

"Okay," Regulus said slowly. He had the feeling he'd been lied to, but he wasn't going to press the issue. "What about you? What's your name?"

"Call me -" The man hesitated. "Call me Padfoot."

Another lie. Something was definitely up, and Regulus planned to get to the bottom of it eventually. He had to gain this man's trust first. And he had an entire lifetime to do so.

Regulus soon discovered that his new friend was definitely not what he appeared to be at first. While Padfoot acted like he didn't have a care in the world most of the time, his past was full of pain. Their stories quite strangely mirrored each other. Regulus, the younger son, had earned the favor of his parents when his older brother had rebelled against them. Padfoot had been the oldest son and had distanced himself from his family, which paved the way for his younger brother to step in as the favored son.

"Strange how similar we are, isn't it?" Regulus commented. "We could almost be brothers."

After several seconds of silence Padfoot finally replied. "I suppose we could."

"Merlin knows you'd be a sight better than my real brother," Regulus continued. "My brother was so terrible to me. He didn't understand what it meant to be a part of our noble family. The burden of being the heir should have been his. Instead he chose to rebel and dump it all on me."

"Maybe he had his reasons," Padfoot snapped. Silence followed before he continued in a calmer tone of voice. "I think I understand your brother better than you might think. Having been in his situation, that is," he quickly added.

Regulus, deciding that this subject would be an extremely contentious one between them, turned the conversation in a different direction. "You've never said why you're in here."

Padfoot was silent for so long that Regulus began to wonder if he'd been heard. He was just about to repeat himself when Padfoot finally spoke.

"I betrayed my best friends." The answer was barely above a whisper, but still Regulus heard it. "They trusted me and I let them down. I put my faith in someone and convinced them to do the same." He stood from his seat on the ground by his cell door. "That same person betrayed them and then me. He's the reason I'm here. But I'm the reason my friends are dead."

Regulus wasn't sure what to say to that. It sounded as though Padfoot was heaping the blame entirely on himself for something that wasn't his fault at all. "I'm sorry," he finally settled on. He paused, unsure if he should continue.

"Thanks," Padfoot mumbled. Regulus heard him shuffle into the corner of his cell. "I don't think I want to talk anymore." He sounded defeated, so totally unlike himself. Try as he might, Regulus couldn't get his friend to utter another word for the rest of the day.

Despite their strange shared ability to keep themselves sane, there were still days that the despair of the place got to them. When Padfoot started to feel hopeless, he would go silent for a while. No matter how much Regulus tried to coax him into talking, he wouldn't say a word. He didn't even move around in his cell, didn't bother eating. Regulus always worried about him, but this usually only lasted for a day or two, and then Padfoot would start talking again, sounding better than he had before.

Regulus, on the other hand, had a harder time with it. He could always feel it coming. The nightmares would become more frequent and start to keep him from sleeping, and then the depression would set in. Padfoot always seemed to sense when this happened as well and would start talking almost incessantly. Regulus never really heard what he said, just focused on the sound of that voice. It was the only thing that allowed him to keep holding on and pulled him out of the darkness of his mind within a couple of days.

Regulus began to think of Padfoot as the brother he'd always wanted. He imagined that this was what Sirius might've been like if their relationship had remained the same from their childhood into their teen years. It was just too bad that he'd had to go through this hell to get the one thing he'd always wanted the most – a brother who cared.

Days passed into weeks, then months. Years flew by, barely noticed by the two men. Things seemed to be routine after a while. Regulus started to get comfortable, or as comfortable as one could get in Azkaban.

Then came the day that Padfoot disappeared. Regulus spent agonizing hours thinking that his friend had died in the night and been taken away without him noticing. But when it came time for their first meal of the day, the dementor still opened Padfoot's cell door, only to find it empty. Soon, all of the dementors were in a frenzy, looking for their lost prisoner.

Regulus stared in disbelief at the empty cell across from him. He had never imagined that anyone could escape from this prison, but Padfoot had done it. What bothered Regulus the most was that his friend hadn't taken him along or even told him that he was going to attempt an escape.

Regulus began pacing his cell, something he hadn't done in a long time. But then, he hadn't been agitated like this in a long time. He felt the old hatred bubbling up to the surface. The same hatred he held in his heart for Sirius was now bestowed on Padfoot as well. He felt betrayed all over again, just as he had all those years ago when he'd first come here.

As he paced erratically around his cell, his foot kicked something in the front corner. Something that didn't feel like stone. Stopping mid-turn, he knelt down and reached out into the darkened space. His hands came in contact with paper.

Snatching it up, Regulus held it up close to the bars, trying to decipher what it was in the weak light. It turned out to be a newspaper, the very one that Padfoot had asked the Minister of Magic for when he'd been here a few weeks ago. Regulus knew this because he had helped Padfoot with the crossword. It had been the most fun either of them had ever had together.

Looking closer, Regulus realized there was a message scrawled across the top of the page. Squinting, he was just able to make out the words I'll come back for you. -Padfoot.

The hatred was replaced by hope. Maybe Padfoot really did care. Still, a part of him didn't want to trust this. He'd been betrayed before by those he cared about. What was stopping it from happening again? Why would anyone come back to a place like this for someone like him?

Again time passed, but it passed differently for Regulus. Now it felt like it had before Padfoot had been brought in, before he'd had another person to focus on. The days felt empty and lonely. He found it harder and harder to hold on to his sanity.

And then, the mass breakout happened. Regulus knew something big was happening. He heard that Bellatrix Lestrange, who was one of his cousins, had been one of the prisoners to escape. He knew she'd been deep in You-Know-Who's circle. She had promised him that she'd be able to get him into the upper ranks of Death Eaters, but that had never happened.

Regulus wished now more than ever that Padfoot were still around to talk to about this. He'd told his friend his story about becoming a Death Eater. Had even admitted that he felt foolish for doing so, that he'd never really hated half-bloods and Muggles, but had felt the weight of expectation that his parents had placed on him and had gone along with whatever they said. He'd been pleased when Padfoot had told him of You-Know-Who's downfall.

Regulus wondered where Padfoot was now, what he was doing. Had he joined the newly freed Death Eaters? Regulus doubted that; Padfoot didn't seem the type to fit in with that group. He just hoped he was alright, wherever he was.

Regulus knew that everything was about to change. The entire atmosphere of the prison shifted almost instantly. He heard people shouting and the dementors were nowhere to be found. The dark cloud that had been hanging over the island seemed to disappear slowly.

Regulus heard cell doors being opened and jumped up from his seat on the floor, rushing to the door of his own cell and peering out.

"I told you I'd come back, now didn't I?" Regulus nearly cried with relief at the sound of his old friend's voice. Padfoot stood just out of sight in the few shadows that were left in the place.

"Padfoot!" Regulus exclaimed. "What's happening? Are they releasing all of us?"

"Not exactly," Padfoot began. Regulus listened eagerly as his friend told him about the second war, how You-Know-Who had risen to power once more and been defeated for good this time, and that the Ministry had reevaluated the cases of every single prisoner in Azkaban. Some were being released, while those who posed a real threat to society would remain here, but no longer under the guard of the dementors.

"So, am I...?" Regulus trailed off, afraid to speak the words, as though saying it would make someone change their mind.

"Yes, my old friend," Padfoot finished for him, "you're being released. I vouched for you." He took one hesitant step toward the cell. "But there's something else you need to know."

Regulus's euphoric mood at finally being a free man was taken down a couple of notches by this statement. Something wasn't right. "What?" he asked hesitantly.

"I haven't been exactly truthful with you," Padfoot admitted. "There's something you should've known about me from the first time we spoke, but I knew if I told you, you'd never speak to me and I would never get the chance to have a good relationship with you again. Even if it was founded on a secret, I'm glad we were friends. I just want you to know that."

"What are you saying?" Regulus asked. "What secret-" Regulus stopped speaking as Padfoot stepped out of the shadows. He felt the blood drain from his face as he recognized his brother. Though aged nearly twenty years, Regulus could never forget that face.

Regulus wanted to lash out, to call Sirius every horrible name he could think of, yell at him. He'd been deceived and it made him feel like a fool for not seeing it before. That appraising look that had seemed so familiar in the beginning had been bestowed on him before. Why hadn't he known it from the start?

Then it occurred to him that not only was this his brother, Sirius Black, standing before him, but Padfoot, the man who had become his best friend during the darkest period of his life. Sirius could've chosen to make his life even more miserable while he'd been in the cell across from his younger brother, but instead he'd decided to befriend him. Sirius had helped him keep from drowning in the sea of madness that had engulfed nearly everyone else around them.

"I understand if you're upset with me," Sirius said, breaking the silence that had been hanging in the air for the past few minutes. "But I want you to know how sorry I am. I didn't care about anyone but myself when I went off to Hogwarts. I didn't want anything to do with my family." Sirius took out his wand, waved it at the cell door, and stepped back as it swung open. "I don't know what possessed me to try to have a relationship with you while we were here together. Maybe it was guilt or maybe I just wanted to have one friend in this awful place." He held his hand out, palm up, toward Regulus. "I don't blame you if you can't forgive me, but if you can, I want to help you get your life back together. I want to be the brother I should've always been."

Regulus looked from Sirius's hopeful face to the hand outstretched before him. He deliberated for only a moment before taking a steadying breath and putting his hand in Sirius's. "You aren't the only one who messed this up. If you're willing to give me a chance, then I can do the same for you."

Sirius pulled his brother into the first embrace they'd ever shared. Regulus felt truly at peace for the first time in his life. He knew that there was still a lot for them to work through, but he was willing to do whatever it took to finally have the kind of relationship with his brother that he's always wanted.