Lir was a member of the Tuatha de Danaan – an Irish clan. After the battle of Tailltin the Tuatha de Danaan chose a king for themselves and much to Lir’s dismay the clan chose another member. The kingship was given to Bodb Dearg who to appease Lir gave one of his own daughters, Aoibh, to him in marriage. Aoibh bore Lir four children: one girl, Fionnuala, and three sons, Aodh and twins, Fiachra and Conn. Unfortunately Aoibh died soon after and Lir, not wanting his children growing up without the love of a mother, married Aoife, King Bodb’s second daughter. There was honour and affection with Aoife for her sister's children and indeed no person at all could see those four children without giving them the heart's love. Nevertheless, a fire of jealousy was kindled in Aoife, and she grew over time to dislike and even hate her sister's children. One day, overcome with hatred, Aoife took Lir’s children to Loch Dairbhreach, the Lake of the Oaks, and bade the children go out and bathe in the lake.
As soon as Aoife saw them out in the lake she struck them with a druid rod and put on them the shape of four swans, white and beautiful. Each child was tied to the other with silver chains to ensure that they would stay together. Realizing what she had done and overcome with remorse, she attempted to release the spell but could only ease their distress by enabling them to speak and sing and to remain as swans for 900 years. As swans, the children had to spend 300 years on Lough Derravaragh (a lake near their father's castle), 300 years in the Sea of Moyle, and 300 years on the waters of Irrus Domnann. Also, to end the spell, they would have to be blessed by a monk. When their time was over the swans were attracted by the ringing of a bell rung by a monk living in Allihies village in the Beara Peninsula. They came ashore and were changed back into their human form. The children were by now old men and women – after being baptized by the monk they immediately crumbled to dust.