Yannael was one of the three children of the Abhorsen Tyriel. Despite being his last surviving child, she did not become Abhorsen-in-Waiting, a title which instead was passed on to her relative Belatiel.
Daughter of the Abhorsen and sister of Jaciel and Teriel, Yannael disowned her sister following her Fury driven killing of their brother Teriel, not knowing that Teriel had been possessed by a Dead creature. When Jaciel's daughter Clariel pointedly stated to her that her own sister had died, Yannael off-handedly remarked that Jaciel had been dead to them long ago.
Out of Tyriel's three children, Yannael was perhaps the most like him, spending her life dedicated to hunting. After her father's death, it is unknown what happened to her.
Like her father, Yannael was an expert hunter and horsewoman, and likely skilled with sword and bow. Like her father, she also disliked entering the Abhorsen's House.