The group - whose fathers all serve with the Armed Forces - have been assembled after a nationwide talent hunt and will sing the official 2013 Poppy Appeal single.
And the newly formed combo, called The Poppy Girls, will also perform in front of The Queen at next month's Festival of Remembrance at the Royal Albert Hall.
With a TV audience of more than six million viewers - and such a poignant record - hopes are high that the girls will mark their recording debut with a huge chart hit.
The girls - Megan Adams, 10, from Stirling, Florence Ransom, 10, from Petersfield, Alice Milburn, 13, from Portsmouth, Bethany Davy, 15, from Dartford, and Charlotte Mellor, 17, from Cambridge - were picked from around 1000 hopefuls.
The Royal British Legion and Decca Records worked together to recruit the group, made up of children who have a parent or sibling serving in the UK or overseas. The children represent the Royal Navy, the Army and the RAF.
Charles Byrne, the Legion's head of fundraising, said: "This is a hauntingly beautiful track sung by a group of girls who know what it means to have family members constantly placed in harm's way.
"We have a major theme in this year's Poppy Appeal around families, so there is no more powerful way of reflecting that than through the voices of these exceptionally talented young people."
The girls - who have juggled school and college commitments with their work in the studio - have recorded the Regina Spektor song The Call (No Need To Say Goodbye), which will be released on Remembrance Sunday, November 10.
Dickon Stainer, the president of Decca Records, said: "When you hear these young kids talk about their families and the sacrifices they make growing up in a Forces family, you do wonder how such young shoulders can carry the burden of the constant stress and anxiety."
He added: "Quite simply this record is beautiful."
The Festival of Remembrance on November 9 will also be broadcast by BBC1.