A traditional Irish lullaby. This version below sung by Róisín Elsafty.

From joeheaney.org

Well, this is an old lullaby they all sang – Seoithín, seo hó, mo stór é mo leanbh. Now, I remember my grandmother singing this for my youngest sister, and she used to hum…after she sang the verse, she used to hum, too. Something like this. Now, telling the little child that the fairies was on top of the house ready to take him away if he didn’t close his eyes. If he closed his eyes, everything was alright. But, as I said before, sometimes it worked – sometimes it didn’t. But this is what they used to do.

The practice of humming, or crónán, is associated with lullabies and other types of ‘private singing.’ For a lullaby-song in English, see ‘The Fairy Boy’. As Joe explains on a number of occasions, there was a belief that children were in danger of being abducted by fairies and exchanged for an old or sickly fairy – a ‘changeling’ – that would inhabit the child’s body, and soon die. For this reason, threats about fairies were sometimes included in lullabies in order to persuade the child to close his eyes; see also ‘Dún do shúil’ (a fragment of which Joe also sings here) and ‘Tháinig bean chois leasa.’ Other items from Joe’s repertoire which relate to the belief that people can be stolen by the fairies include The Changeling, The Fairy Frog, The Fairy Greyhound, The Woman Who Came Back from the Dead and Why children are stolen by the fairies.