Remus.

I know what you must think of me. I don't blame you. Sirius'll probably show you anyway but in case he doesn't read it at all, I have enclosed a duplicate of the letter I sent him, to ensure that he hears. Don't try to hide this from him - these are my last words to the both of you, and estranged or not he'll want to hear them.

I have so many regrets when it comes to Sirius. Not standing with him, not supporting him more, not doing more to prove that he's still my brother and that I still love him.

But one of my biggest regrets, because it would've sent the strongest message, was not getting to know you, James, and Lily better.

Remus, despite my background, and your unfortunate circumstances, I have never seen myself to be superior to you. On the contrary, it has always been the opposite.
You've been brave, you've been strong, you've persevered, you've endured. You've always been good to everyone, and have always treated my brother like the great man he is. I've never heard you say a bad word about anyone, even me, and Merlin knows I'd probably deserve it.
I envy you for this - a lesser man in your position would've broken long ago Remus, and I've never been particularly strong or courageous.

You're the type of man I wish I could've been. What I would have aspired to if I made it out of this.
Which is why I approve of you for Sirius. He's always been different around you. You make him a better person.
He really does love you, you know. I've noticed recently that the way Siri acts around you, and the way I act around Barty, is nearly identical.

I don't know if Sirius will be able to while mourning, but I requested in my letter to him that he try and get to know Barty. I hope that one day the two of them might be buried either side of me - if my remains can be retrieved.
I also hope that maybe you and Siri, James, and Lily can be the surrogate family Barty so desperately needs. His family life is nonexistent, his father is oblivious to any aspect of his son's agony.
I've been the only thing keeping him from breaking. Without that influence I fear for his wellbeing and safety.

Please ask James and Lily to give him a chance for my sake. I know that despite our history we had a mutual respect.
I'm so sorry I never made the effort with you guys. But my sense of self-preservation was always stronger.

Sirius acts extremely rashly when emotionally wounded, and I don't doubt for a minute that he won't at the very least try to find my last whereabouts, at best succeed.
I'd like to think he wouldn't go alone, but you and I both know him better.
Please, stop him from doing anything he'll regret, from making my same mistakes.

Remind him that none of it was ever his fault, and that no blame falls to him. Same goes for Barty.

Thank you all for being the family Siri never had.
All I ask is that you give Barty the same opportunity also.

Your brother-in-law,

Regulus Arcturus Black.

Remus finished reading the letter, and choked on a sob.

Regulus was the only Black family member who had mattered to his Sirius. And to hear that he approved was so damn important to Sirius and himself."Oh Regulus, you mule-headed dolt. Could've saved yourself the trouble and sent these letters years ago," Remus whispered.

Sirius stirred from his position against Remus' chest and mumbled sleepily.
"What was that Pads?"
"Said wha's matter? Heard you cryin'. Then whisperin'..."

Remus chuckled quietly and said "Nothing's wrong. It can wait until you're up to talking, love. Sleep."
"You sleep too," Sirius said as he dragged his wolf down to lie with his head on the pillow. "Not fooling me. You haven't slept while you've been holding me. Rest," he said as he found himself a comfortable spot against Remus' side again, all the while not unwrapping his arms from around the wolf.
"Mmph. Love you Moony."
Remus kissed his head quickly, and whispered "Love you too Siri. Don't ever forget it," before succumbing to slumber again himself.