Ethniu

In Irish mythology, Ethniu (Old Irish , Eithne ; also Ethliu, Ethlinn, and a variety of other spellings – see below) was the daughter of Balor, king of the Fomorians.She is best known as the mother of Lug. Her union with Lug's father, Cian of the Tuatha Dé Danann, is presented in early texts as a simple dynastic marriage, but later folkore preserves a more involved tale, similar to the birth of Perseus in Greek mythology. According to a prophecy, Balor was to be killed by his grandson. He locked Ethniu in a tower made of crystal to keep her from becoming pregnant. However, Cian, with the help of the druidess Birog, managed to enter the tower and seduce her. She gave birth to triplets, but Balor threw them into the ocean. Two either drowned or turned into seals, but Birog saved one, Lug, and gave him to Manannan mac Lir, who became his foster father.
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