Of all the places to find this, I found it in the Celtic Fake Book! At least we have some words. That book calls it A Fairy Plaint, or Ceol-brutha:

Phiùthrag a phiuthar

Nach truagh leat fhéin phiùthrag a phiuthar
O hi o hu o ho
Nach truagh leat fhéin nochd mo cumha
O hi o hu o ho

Nach truagh leat fhéin nochd mo cumha
'S mise bhean bhochd chianail dhubhach

'S mise bhean bhochd chianail dhubhach
Mi'm bothan beag iosal cumhann

Mi'm bothan beag iosal cumhann
Gun lùb siomain gun sop tughaibh

Gun lùb siomain gun sop tughaibh
Uisge nam beann sios 'na shruth leis

Uisge nam beann sios 'na shruth leis
Ged's oil leam sin cha'n e chreach mi

Ged's oil leam sin cha'n e chreach mi
Cha'n e chuir mi cha'n e fhras mi

Would you not pity me, o sister?
Would you not pity me my mourning tonight?

My little hut

Without a bent rope or a wisp of thatch
Water from the peaks in a stream down through it

But that's not the cause of my sorrow