For the Big/Lil' Sis Team Prompts where I had to use 5 of 7 prompts – Character: Tonks, word: quiet, quote: "The only way out of the labyrinth of suffering is to forgive" – John Green, season: spring, item: mug of hot chocolate, phrase: took my breath away, genre: angst.

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Spring 1976

It's the Easter holidays, and you don't know why your brother even comes home anymore because arguments break out every time he's home. You want to intervene in the fight, but you know that it'll just make it worse on him. Instead, you lay on your bed, your hands tucked behind your head as you try to drown out the sounds of shouting coming from the floor below.

After a while, the shouts and the screams cease and peaceful silence descends on the house. You hear Sirius' soft footsteps as he climbs the stairs. You wait for the quiet knock on your door that never comes. He doesn't come into your room, like he usually does; instead, he slams his door shut and you hear nothing from him for the rest of the night.

It bothers you that he doesn't come to you for comfort after the fight. But it's not like you give him much anyways. He'd pace the length of your floor, talking furiously about your parents, his hands waving in full animation, while you'd just sit there and listen without interruption. He'd then make you promise never to be like them, never to follow their orders without first thinking them through, before he would leave.

Tonight's different. You wonder what changed in him, what made him go to his room instead of seeking you out. A part of you knows that you'll never understand it.

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Summer 1976

You're awoken by a crash. Your door flies open, and your brother stands there. He's wearing dark Muggle clothes, but what catches your eyes is the look upon his face. By one glance, you know that he's found his breaking point, that they've pushed him just a little too far.

"What's going on?" you ask, pretending you don't know what's going to happen.

He crosses the room with three long strides and gathers you in his arms. "It's nothing, Reg," he whispers against your hair. But there's a tone of regret in his voice that you've never heard in it before.

You pull back and meet a familiar pair of grey eyes. "You're lying, Siri," you reply softly. "You're leaving, aren't you?"

Sirius doesn't answer. Instead, he looks at you urgently. "Promise me something, Reg," he says fiercely. "Promise me that you will do everything they want, that you'll be the son I couldn't be."
When you don't, he grabs your shoulders. "Promise me, Regulus."

"Why?" you ask. And he knows why you're asking. He's always told you to go against what your parents had to say, to be independent, to think for yourself. Now, he's telling you to do the opposite, to abide by what they say. It confuses you.

His answer is simple. "You don't need to know why. Just promise me." There's an unidentifiable look in his eyes that makes you promise him without an explanation. "Thank you," he murmurs against your hair as he pulls you in for one last hug.

And then he leaves you by yourself to fare against your parents and the rest of the world.

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Autumn 1976

The next time you see Sirius is at the start of the term. He looks happier than you've seen him since before his Hogwarts days. He's surrounded by his friends – who your parents hated because they are blood traitors and Half-bloods – and you think that they are now his family. That the blood you share means nothing to him now.

He meets your eyes from across the hall and there's a certain sadness that you know will never leave them. And in those moments you wonder if he ever regrets leaving you, if he ever considered taking you with him. But somehow, you know that he never thought about taking you, about saving you as well as himself.

And a tiny part of you hates him for leaving you behind. The other part just wishes that he would've taken you with him because being with him is better than being with your parents.

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Winter 1976

You finally understand why Sirius made you promise to behave. As you feel the nerve endings in your body alight, you know that Sirius was trying to protect you, even as he was leaving. He was always protecting you when he took the blame for the things you did wrong.

Without him here, you finally experience the Cruciatus curse first-hand. The pain is enough to take your breath away and make you fall to your knees. Your father stands above you, his wand unwavering in his hands. He lets the curse run its course through your body, and gives you a look of disapproval as you scream.

"You are weak," he growls at you. "Just like your –," and he breaks off. It's been months since either of your parents have uttered Sirius name, and it's as if he's dead to them. When the curse lifts, your father looks at you with the same grey eyes as Sirius. "Maybe next time you'll remember not to talk back. Dismissed."

You struggle to your feet, and gingerly make your way to your room; the whole time, you curse Sirius for not being there to protect you.

A/n = thanks to Kelly for beta-ing this for me!