Katrina has the job of greeting and helping strangers understand the community. She was raised in Vault 15, in which she had a very boring life. Over time the vault that Katrina lived in became overcrowded, forcing the residents to leave. Many of them gathered their supplies and ventured out into the wastes with no knowledge of the outside world. Apparently, a new life would begin for everyone. However, some stayed behind in the vault which was later attacked by raiders. She escaped the vault and was wounded, but was found by residents of Shady Sands. She has stayed there ever since.
The intention of the developers of Fallout was likely to include her as a tutorial character considering her dialogue is focused around explaining a few fundamental game-play systems, including bartering, healing and the First Aid and Doctor skills.
Katrina will give the dialogue concerning abduction of Tandi during the Radscoprion quest. Similarly, during the quest to rescue Tandi, she will instead have the dialogue concerning dealing with radscorpions.[verified]