Here it is, as promised. My mother used to sing this when my sister and I were little.

Helen

TWO LITTLE GIRLS IN BLUE
Words and music by Charles Graham, © 1893.

An old man gazed on a photograph, in the locket he'd worn for years;
His nephew then asked him the reason why that picture had caused him tears.
"Come listen," he said, "I will tell you, lad, a story that's strange but true;
Your father and I, at the school one day, met two little girls in blue.

CHORUS: Two little girls in blue, lad, two little girls in blue,
They were sisters, we were brothers, and learned to love the two;
And one little girl in blue, lad, who won your father's heart,
Became your Mother, I married the other, but now we have drifted apart.

"That picture is one of those girls," he said, "and to me she once was a wife,
I thought her unfaithful, we quarrelled, lad, and parted that night for life.
My fancy of jealousy wronged a heart, a heart that was good and true,
For two better girls never lived than they, those two little girls in blue."

Copyright by Francis, Day & Hunter.

Francis & Day's Popular & Community Song Book for all Occasions. Sydney, Albert & Son.