To my brother, for the final time,

This is the last letter of mine you will read, I'm sending it to you to explain and to prove to you that I never forgot. I don't know why I feel obliged to do this but I think I just want to put things to rest before I go. Before I joined the Dark Lord I wondered about your reaction the difference being that I based you not as my brother but as one of your self-righteous Gryffindor friends; I forgot that you had not deserted me as you had the rest of our family, forgot that instead of loving us all you loved only Andromeda, Alphard and I and even then you hid it well another thing you hid was your Slytherin sense of self-preservation; you rarely let that one out even when you were alone and didn't need a mask you would fight, but there have been times when I have seen it, your lies: to your friends about what went on at home, to our parents about what went on at school, to everyone about who you truly were. I wonder if anyone except your friends and I ever really saw behind your mask.

But back to your reaction, as I said I had forgotten that you loved me; I had always assumed that I was held in the same contempt as the others but I was wrong. When I told you, you did not hit or curse me as almost everyone who has seen your temper might think, but sank onto a chair and stared I admit I was rather surprised until you pulled me off the bed and yanked my sleeve up but you barely saw the mark before releasing me another thing I hadn't expected was you to cry, I expected that you would rant and rage about goodness and love and morality and how life is good and other crap that Blacks aren't taught. Eventually of course you did shout at me and try to make me change my mind and that was when I first properly realised that you really did believe in all that before that afternoon I thought that it was a mask you wore so you could keep your friends. I never thought that anyone who was raised as we were could ever really deny it all, not when they had grown up knowing what happened to traitors and filth. When you had finished shouting our parents opened the door; they had probably been listening the whole time and then...well you know what happened next, and once you were gone I felt guilt and fear like I hadn't for ages: guilt at causing you all this pain both external and internal and fear for our futures; mine because right there in that moment I saw what would be expected of me for the time I was in servitude – for the rest of my life. And you because I knew that you hadn't told anyone about how they treated you and I knew that you were scared of them deserting you if they found out how truly dark the Blacks were.

And now I have been in the Death Eaters for a few years and I've realised that you were right about them, about us, about me. And I've changed, really. Now I know that you're not going to believe that just from this letter and that's why I'm not telling you face to face; because you'll arrest me before I've had a chance to say anything not that I'd really have that much to say just that I've changed my mind and I've got some information: I'm attaching as many names and future plans as I know of to this letter. The other thing I know – the one I plan on dying for is going to stay secret because I don't think you'd believe me and even if you did you would try to stop me and go instead – just like a Gryffindor, and this is something I want to myself it is my revenge to the Dark Lord and if my plan works it will help the light side even if they and you will never know.

So really what I am trying to impress upon you in this letter is that I've changed, that I love you, that you were right all along and most importantly, but not in a bad way, GOODBYE. I hope your life turns out better than mine.

Yours,

Regulas Arcturus Black

As Sirius finished the letter he noticed that he had been crying, in fact the tears were still dripping down his face and into the dust that coated his brother's old writing desk.

There was a sharp pain in his chest and a single thought running through his mind: You should have told me. I would have listened. You were never a Death Eater to me; you were always just my little brother who needed protecting. I wish I could have protected you Reggie.

He spoke the last sentence out loud and with the tears coming faster than ever, he folded the letter in half and tucked it into his pocket; it was all he had left now – all that remained of his brother.