Once, Aengus was troubled by the dream of a young maiden, He instantly fell in love with her and became love sick. He told his mother Boann and she searched the whole of Ireland for the maiden, but after a year she still had not found the maiden. Then Dagda was called and he searched Ireland for a year, and still did not find the maiden. Finally Bov the Red, king of the Dananns in Munster and Dagda's aide, was called to search and after a year he found the maiden.
Aengus was taken to the lake of the Dragon's Mouth, and there he saw 150 maidens all chained with gold into pairs. He spied her at once and her name was Caer, the daughter of Ethal and Anubal, a prince of the Dananns of Connact. On November first she and all the other maidens are transformed into swans for a year. He was told if he could identify her as a swan he could marry her. On November 1 Aengus went out to the lake and called to his love, and once he had found her he then turned in to a swan himself and joined her. They flew off together singing such a beautiful song that all who heard them fell asleep for three days and nights.
Aengus had a son called, "Diarmuid Ua Duibhne" or Diarmuid of the Love Spot. One night while hunting Diarmuid met a maiden who made a magic love spot appear on his head, and from then on no woman ever looked upon him with out falling in love with him.