Not by Dag?
So another shot in the dark (for the bonus; a good thing Blackwing got the main question, I had no idea...)
Cazaril; in Curse of Chalion.
Something= being somehow involved in the Daughter's design...
That's a very broad "something", that might mean surviving Roknari captivity and the ordeal of the trip home, if very early in the book; surviving the night in Fonsa's tower, if about that part of the book; surviving Martou's sword, if very late in the book... or earlier in time, surviving the siege of Gotorget, if in a reminiscence.
I'm cheating, he?
It just that I feel that this "breath" stuff is related to survival (as in Miles' case, in a broad sense: Memory is all about survival, if I had only thought about it; I was thinking in terms of Mirror Dance itself, or Vor Game during the "limbo" epoch, after Kyril but before Victor Rotha, but of course it was not there)