In 2077, after being parted from her dad (probably unwillingly), Janey was given a pip-boy by her mother, and she was taken into a vault. This vault was set up with cryosleep pods, and Janey was put into cryo for 200 some odd years, give or take (depending on how old she is when she comes out of cryo; itโs flexible in this AU).
When she comes out of cryo (be it because that was when the pods were supposed to wake her up, or some sort of malfunction, or some other reason), the world is completely different to the world sheโd left behind. And sheโs a child. Possibly a child
alone. Left to fend for herself.
Leaving this part pretty vague for potential exploration in RP, but she flounders HARD at first because sheโs a 7 year old (at the oldest 10) on her own with NO knowledge of a post-bombs world. Sheโs got a steep learning curve and sheโs been dropped into the fucking deep end. She probably survives by being scrappy and learning to adapt QUICK, until she at some point stumbles across some kind souls in the Wasteland, most likely NCR folks. Which helps her learn all the skills that she knows, save for the whip skills, which she adapts from the roping skills her dad had been teaching her before it all goes to shit.