Little is known about Lygeia's past before Grettir mated with her, but it is known she had settled in Grettir's hallow after he retired from being an acolyte. During that time, she laid an egg and lived peacefully until the night of its hatching. Then the Pure Ones attacked. Lygeia teamed up with Grettir to defend the egg. During the skirmish, Allomere, who was very close to her mate, appeared, killed both her and Grettir, fled before the Guardians arrived and rescued the hatchling, and carried him to the Great Ga'Hoole Tree, where he was raised and named Shard after a chip of egg stuck to his beak.