You aren't the father of your son
His father is the other
Of one thing I am certain
That I am his mother
He was exchanged in fair trade
For unwilling contribution
They stole my unborn children
Then paid with retribution
Of this I cannot tell you
Or any of this world
The world is all illusion
I saw it all unfurled
He could conquer all of Ireland
He could rule the Egypt land
He could start the Roman Empire
Bury continents with sand
Of this I haven't spoken
To man or god or beast
To friend or foe because I know
What is to be his geist
His geist is told to noone
They told me in my dream
Of a gift ne'er can be given him
Or ne're 'gain will he be seen
So be his father well my love
Give to him your heart
And I will grieve forever
Long long after when we part
Cuchulain's father is said to have been one of the "gentry" which means one of the fairy folk.