In the Lichtbob's Lassie

I'll dye my petticoats red
Yface them with the yellow
Tell the dyster's lad
I follow a Lichtbob fellow

It is said that, as red was a dye colour that was cheap to produce, it was often used to dye women's flannel petticoats.
These being the garment of the poor were often attributed to prostitiutes but would also probably have been worn by the camp followers - the numerous women (and their children!) who followed their husbands and partners on campaigns and often provideding the services of laundresses, mending clothing, cooking meals and nursing the wounded.

'Camp followers were not from any select social class. Officers' wives and mistresses accompanied them on the march. Women of more learned background, however, were also able to provide services such as copying correspondence, knitting and managing field hospitals

Women and children's names were submitted to the commanding officers and these camp followers were entitled to receive a portion of a ration.
Those women less formally affiliated with the soldiers relied on the soldier to give up a portion of his own rations or she had to fend for herself. Quite often, women who suddenly found themselves far from home and widowed quickly remarried one of her husband's comrades'