Author: Estyrien al'Halien
Cetalia Delarme was an Aes Sedai of the Blue Ajah when Moiraine and Siuan were newly raised. She was head of the Blue eyes-and-ears (NS, Ch. 12). Since we know that Siuan ran the Blue eyes-and-ears before she became Amyrlin Seat, it is possible that Cetalia is dead, especially since she was old during "New Spring" (NS, Ch. 12; TFoH, Ch. 27).
Cetalia was almost as strong in the One Power as Moiraine and Siuan when they reached their full potential. However, while they were newly raised, Cetalia was stronger than them; it took three or four years before they became stronger than her (NS, Ch. 12, NS, Ch. 18). Anaiya was nearly as strong as Cetalia (NS, Ch. 12).
Siuan was Cetalia's assistant for her work with the eyes-and-ears and was one of the few sisters who knew of her job (NS, Ch. 12).
There was no point in protesting again. The bloody woman had already made it clear that two protests in succession came dangerously close to rudeness in her book. Bloody, bloody woman! (Siuan about Cetalia; New Spring, Chapter 12)
"From the moment I arrive it's 'Find this, Siuan' and 'Do that, Siuan' and 'Aren't you finished yet, Siuan?' Cetalia snaps her fingers and bloody well expects me to jump." (Siuan about Cetalia; New Spring, Chapter 14)
Another three or four years would pass before Siuan gained enough strength to tell Cetalia that she was leaving the job as Cetalia's assistant. There would be snow at Sunday before the woman let her go short of that. (Moiraine about Cetalia; New Spring, Chapter 18)
"Cetalia will use me to caulk drafts for running off without leave," she grumbled. "Burn me! Hung out on a drying rack in the Tower! I'll be lucky if she doesn't have me birched!" (Siuan Sanche about Cetalia; New Spring, Epilogue)