Petara

Petara is the oldest, and perhaps the most inscrutable, Daughter of Earth Colony. Many of the others think her only a hated apostate and heretic, and it is a mystery to them why she survived the purges of the White City, or why Garaka and Nerrine suffered her to live among them.

But those in the know-- Kellin, Nerrine, Lask, Fenn, and Danalee-- know that she was the spymaster for both the Mothers and Daughters, a double agent that delivered the White City to Garaka's forces.

Her motives remain mysterious, even to her puppets, but like Ress, she is always playing at a game of her own design. She serves as one of Nerrine's primary advisors, Other than tending her own garden just outside the ship, she does not venture out into the world or interact with its natives.

The Genetics War
Petara was spymaster for the High Imperatrix of the White City, fighting on the side of the Mothers, and from that position recruited the empath Lask, the whore Nerrine, and the assassin Danalee, among others. It is unclear at which point she began conducting espionage operations for the Daughters, instead of against them-- whether it had been all along, or if there had been some kind of switch. But it was Petara's network that gave Garaka's armies the White City.

Earth Colony
Petara largely kept to the background in the first book.

To Bell The Cat
Petara tells Nerrine the truth about Earth Colony: that they have been sent here to die like the Heretics of Cydonia before them. (Secrets of Cydonia)

Petara threatens Kellin, revealing her knowledge of Ress's involvement in the death of Jarissy. They are overheard by Lask, who reports this information to Nerrine. (Walking Wounded)