Kersey was the wife of Ferdimond de Mayne, mother of Dauncey de Mayne, and the twin sister of Dauncey, with whom she was a galloper for the Long Patrol under Lady Melesme. In an unfortunate ambush by Gulo the Savage Horde, Dauncey was killed by two arrows. Kersey would have gotten hit as well, but Brigadier Buckworthy Crumshaw tackled her, taking the arrow in his shoulder. After the death of her brother, Kersey was notably less chipper and even somewhat spiteful and vengeful.
She later gave her brother's sling to Ferdimond de Mayne.