OK that really had me busting a gut.
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Now many many years ago when I was twenty-three
I was married to a widow who was pretty as can be
This widow had a grown-up daughter who had hair of red
My father fell in love with her and soon they too were wed
Oh I'm my own grandpa
I'm my own granpa
It sounds funny I know,
But it really is so
Oh I'm my own grandpa
This made my dad my son-in-law and changed my very life
My daughter was my mother 'cause she was my father's wife
To complicate the matter even though it brought me joy
I soon became the father of a bouncing baby boy
My little baby then became a brother-in-law to Dad
And so became my uncle, though it made me very sad
For if he was my uncle, then that also made him br'ther
Of the widow's grown-up daughter who was also my stepmother
Father's wife then had a son who kept them on the run
And he became my grandchild, for he was my daughter's son
My wife is now my mother's mother and it makes me blue
Because altho' she is my wife, she's my grandmother too
Now if my wife is my grandmother, then I'm her grandchild
And every time I think of it, it nearly drives me wild
For now I have become the strangest case I ever saw
As husband of my grandmother, I am my own grandpa