A folktale told to John O'Donovan by Shane O'Dugan of Tory Island in 1835 recounts the birth of a grandson of Balor who grows up to kill his grandfather. The grandson is unnamed, his father is called Mac Cinnfhaelaidh and the manner of his killing of Balor is different, but it has been taken as a version of the birth of Lugh, and was adapted as such by Lady Gregory. In this tale, Balor hears a druid's prophecy that he will be killed by his own grandson. To prevent this he imprisons his only daughter in the Tór Mór (great tower) of Tory Island. She is cared for by twelve women, who are to prevent her ever meeting or even learning of the existence of men. On the mainland, Mac Cinnfhaelaidh owns a magic cow who gives such abundant milk that everyone, including Balor, wants to possess her. While the cow is in the care of Mac Cinnfhaelaidh's brother Mac Samthainn, Balor appears in the form of a little red-haired boy and tricks him into giving him the cow. Looking for revenge, Mac Cinnfhaelaidh calls on a "leanan sídhe" (fairy woman) called Biróg, who transports him by magic to the top of Balor's tower, where he seduces Eithne. In time she gives birth to triplets, which Balor gathers up in a sheet and sends to be drowned in a whirlpool. The messenger drowns two of the babies but unwittingly drops one child into the harbour, where he is rescued by Biróg. She takes him to his father, who gives him to his brother, Gavida the smith, in fosterage.