Hope this is the one:

KEEP THE HOME-FIRES BURNING
Words: Lena Guilbert Ford, Music: Ivor Novello
New York: Chappell & Co., ©1915.

1. They were summoned from the hillside; they were called in from the glen,
And the country found them ready, at the stirring call for men.
Let no tears add to their hardship, as the soldiers pass along,
And although your heart is breaking, make it sing this cheery song:

CHORUS: Keep the home fires burning While your hearts are yearning.
Though your lads are far away, they dream of home.
There's a silver lining Through the dark cloud shining.
Turn the dark cloud inside out till the boys come home.

2. Overseas there came a pleading: "Help a nation in distress!"
And we gave our glorious laddies; honour made us do no less.
For no gallant son of freedom to a tyrant's yoke should bend,
And a noble heart must answer to the sacred call of "Friend."