This is Sean Whalen (prion).
When I looked over the Whorl Archives here, I was amazed to learn that Blood's father was Patera Pike. I also read the discussion of clues in the text about this. I don't have much to add, but when I looked over the book, the first thing I noticed was that Blood only asked Silk if Rose and Pike were still at the manteion. I guess if one kept this in mind, as Wolfe would probably want a reader to, it could be a partial clue after we learn that Rose was his mother and that he knew this. Of course, I doubt that anyone could remember this or even connect it without knowledge beforehand.
An even less significant clue, which I wouldn't even mention if the author weren't Wolfe, who loves clues with names, but all three of their names begin with similar letters, each a specific one: P R B. As I said, very slight.
prion