Aethra was the mother of Theseus. Aegeus, Aethra's ex-lover and Theseus' father, had left his sword under a huge rock and told Aethra that when their son would grow up, he should move the rock and bring his weapons back. Although distraught by the idea of her son leaving, Aethra told her son that he would come to know his father if he could move the rock. Theseus grew and moved the rock, and left his mother to seek his father.