Kelly was a member of the UNSC Marine Corps and an Orbital Drop Shock Trooper in the 105th Shock Troops Division. She participated in the Battle of Ariel in January 2552 under the command of Master Sergeant Frost.
Deployed to Ariel following a distress call, the ODSTs landed and investigated one of the planet's two settlements, soon becoming under attack by the Covenant. After the colony's reactor complex was destroyed, Frost decided that they head to the planet's other settlement four kilometers away. On their way to the settlement, Kelly, Jambo and Fielding became noticeably fatigued, prompting Frost to order them to form up their ranks. Kelly was among the ODSTs who survived the battle, as the Covenant abandoned the planet directly after the destruction of the Forerunner construct known as the Knowing.
- Halo: Helljumper (First appearance)