He found Harry after the pudding, when people had risen from the table and the room had relaxed into standing conversation.
Harry was at the window, looking down at the alley below — the stillness he had in the moments between, when the conversation had paused and he was deciding where to be next. Ron stood beside him and handed him the photograph first, then the book.
Harry looked at the photograph for a long moment. The Burrow gate, the morning light, the expression on his own face that he would not have known was there.
'When did you take this?' he said.
'Yesterday morning. Kitchen window. You didn't know.'
Harry turned the frame over and read what was written on the back. He was quiet.
'I look like I belong there,' he said. Not with the quality of someone saying something they wanted confirmed. With the quality of someone encountering evidence of something they had not allowed themselves to fully believe.
'Yes,' Ron said. 'You do. Because you do.'
Harry looked at the photograph a moment longer. Then he set it carefully on the windowsill and looked at the book, which he read the cover of with the focused attention of someone assessing whether a thing was what it appeared to be.
'Non-verbal casting,' he said.
'Practitioner's guide. Not theoretical. The man who wrote it spent thirty years teaching duelling and had no patience for anything that didn't work under pressure. You'll read it differently than I do — you think with your hands rather than your head, in the moment. The book accounts for that.'
Harry looked at him with the expression he had when he was receiving something he hadn't expected and was still deciding how to hold it.
'Happy birthday,' Ron said.
'Thanks,' Harry said. Then, after a pause that had its own quality: 'I've never had a birthday like this.'
Ron nodded. There was nothing to add to that, so he added nothing.
Sirius found Harry at the window a few minutes later, as Ron had known he would. Ron moved away without making a thing of it.
He did not attempt to overhear the conversation. He had a sense of its shape from a distance — the quality of Sirius's posture, which was the posture he had when he was saying something that mattered and had decided to say it directly. Harry's face, which had the expression Ron had seen in the photograph, the one that was still learning how to receive things.
He took no photograph of this.
Later, after Sirius had moved away and Harry had stood at the window alone for a moment, Harry found him across the room and looked at him with the expression that had resolved into something settled.
Ron raised his eyebrows slightly.
Harry nodded once, with the quality of someone who had been told something they had needed to hear and had received it properly.
That was sufficient.