Another separate theory I have is of Berelain sur Paendrag being a relative of Clan Chief Rhuarc, possibly a daughter. Notice, how they interact while ruling Cairhien together and other places. Also note how other people act around them and what their thoughts are. Berelain gets extremely unusual specialized treatment from the Wise Ones(note: Book 6, hardcover p. 658). Also Book 6, hardcover, p 667 at the bottom has some wording there that is suggestive of this theory.