Here's the added "third verse" to DANNY BOY as I recall it:

But should I live, and should you die for Ireland,
Let not your dying thoughts be all of me,
But breathe a prayer to God for our dear sireland,
That He will hear, and He will set her free.
And I will take your place and pike, my dearest,
And strike a blow, though weak that blow may be.
To help the cause to which your heart was nearest,
And you will rest in peace until I come for thee.

Here are some notes:
Although the tune is Irish (Derry Air) the first, and original two verses were written by an Englishman in 1912. The last verse was written by an unknown Irishman. The familiar tune was composed by Rory Dall O'Cahan in 1855 as a lament for his ancient clan. The Englishman was Frederick Weatherly, a prominent lawyer from London.