Tanisia Idaho was the fourth and last daughter of Murbella and the final ghola of Duncan Idaho. Like her sister, Gianne Idaho, Tanisia was completely unaware of her parentage, and served the Sisterhood for years on Chapterhouse in obscurity as an acolyte. During the advent of Kralizec, Tanisia was sent out to raise humanity's morale against the onslaught of the Thinking Machine armada, by becoming part of the Sisterhood's final Missionaria Protectiva.