If Remus had been able to do so, Regulus probably would have let him.

Regulus expects someone to be in the room with Sirius, but somehow he hadn't expected it to be Remus. Remus who is facing away from him on a course back toward the bed, who Regulus can recognize just from the shape of his shoulders. He feels sharp and broken and bitter - the little resolve he'd managed to pull together drains out of him like so much water and he stills as soon as he's inside the room, breathing out ragged and weak.

"Sirius," he croaks out, but he chokes on the word as it leaves his throat because he can see his brother there on the bed, looking small and it's his fault. Then: "Remus." It's hoarse.

He hasn't moved for his wand. He probably should have.