Jenny Winters was born in Vermont, around 2176. Her mother was a telepath, and her father was a normal.
The family moved around very frequently because her mother was trying to avoid detection. Eventually her father left the family - her mother would never speak of it, but Jenny is convinced anyway that he must have left because he got tired of all the moving, and tried to turn her mom in to the authorities. He left when they were living in England - Jenny's mom took her and ran, first to India, then to Amazonia.
Jenny never saw her father again.
Her mother worked for a company "under the table" as an unregistered telepath, doing illegal scans. They paid little, Jenny and her mom had to live where they said, and Jenny had to be secret about the whole thing. They lived in a small, dark room with one bed and a kitchenette, and they weren't far from the beach. (And they had dishes, which Jenny had never had before.)
Her mom agreed to work illegally for the company because they wouldn't test Jenny for telepathy in school. Jenny developed telepathy at nine, but because she was never tested, the Corps didn't know about her. Working illegally for the company, Jenny's mom had to put up with a lot of abuse, but she did it anyway out of some misguided belief that this life on the run was better for her daughter.
When Jenny was about ten, her mother was murdered by the company. Who can know why - some deal went south, and they killed the teep, or some deal went as planned, and they killed the teep to cover it up. Some men came from the company to tell Jenny her mom was dead, but she dissociated and didn't listen and then she didn't believe them.
They said they would "take care of her," but they sold her into sexual slavery to a wealthy man named Achilles Robert Farmer. He locked her in a back room, often naked, and assaulted her regularly. He would bring to her places and force her to feel other people getting beaten up and stabbed, and then make her telepathically project those feelings to him, because he got a rush out of it. He would also force her to watch people have sex, and feel that, and project those feelings to him.
And he also raped her himself. He would rape her while forcing her to make him feel his raping her. And he gave her alcohol - Jenny would drink hard liquor when she could get it, to drown out the pain she was forced to live, day after day. She also sniffed paint - she took any drug she could get her hands on, though she didn't have access to much.
She didn't go to school. She had no one to turn to for help, because there was no one who even knew she existed, other than her captor and those associated with him.
The Corps couldn't rescue her because they didn't know she existed. If she'd been tested in school and registered, and then she disappeared, then the Corps would go looking for her. This is why unregistered teep kids are the most valuable on the black market. In Jenny's case, there was no one looking for her at all - not the Corps, and not normal social services.
Mr. Farmer also worked with the Underground. Maybe he helped them "move" teeps from place to place, or provided them with other assistance. Somehow they found out about Jenny, though, and raided his house. He'd been tipped off and was gone. They found Jenny naked in a back room, and brought her with them as they moved from "safehouse" to "safehouse."
Then they brainwashed her, though it wasn't very difficult given what she'd been through. They told her that the Corps is slavery, and her life with them (the Underground) is like the "underground railroad." (To where...?) They told her that the Corps was like Nazis, and that she should keep a diary because that would make her like Anne Frank, and that if a Psi Cop ever found the diary and read it, would rid the world of an evil man by making him good. When things got tough, like there wasn't much food or clothes to wear or other things, they told her that was the price she and the others had to pay for their "freedom."
She practically worshiped the leaders of the Underground: Matthew and Fiona Dexter, and Stephen Walters, and wanted to grow up to be just like them. She writes, "That's what I want to be [a good resistance leader], too. I don't just want to ride the railroad to some place safe. I want to fight. I want to blow Psi Corps up, completely, maybe EarthDome, too." The Dexters told her not to think like that, teaching her that "we should only blow things up 'when we have to,'" but Walters liked it. In short, they raised her to want to be a terrorist, either to kill people for the hell of it or only to kill people when they "had to," for their twisted "cause," depending on who was setting the tone.
Things started to go south when some rogue groups splintered off, tired of the Dexters and Walters, and wanting to do things their way. Things got worse when a rogue cell bombed a train station and killed lots of normals. The Underground leadership decided to go, well, underground - literally - to one of their "headquarters," a series of caverns in Tennessee that back in the 2050s had been an underground hotel and tourist attraction. Jenny stayed at the "safehouse," but they brought over a hundred other people with them, many of them children.
Some had run away voluntarily, like Jenny's mother had long ago, but many were children and young adults who had been kidnapped as part of the rogues' plan to "save" the children. The truth, however, was that the rogues had no greater "plan" at all to make life better (as they saw it) for telepaths - they kidnapped children, they blew up sleepers factories and Psi Corps facilities, they got Psi Cops abducted by normals and forced into slavery in remote places, they murdered Psi Cops and Corps personnel ("Another time Fiona and Matthew were captured in the Central African Bloc. Stephen just walked into the holding station and killed everyone there, like an avenging angel."), but it was just about selling "hope." Join us, kill people, and you can have hope. As Fiona puts it, one day: after all the killing and kidnapping and terrorism, "it would all be over, and they could step into the sun."
Just like that. No consequences for all the murder and mayhem. Normals would wake up and say, "oh! these people were right all along, let's change all these laws right away!"
(The Underground doesn't fight a dual war, part political and part "kinetic"; they don't have a network of sympathizers who pressure the government in non-violent ways, they don't engage in any kind of education or propaganda campaign, they don't work with NGOs - it's all about violence as the "solution" to normal prejudice, violence and blaming other telepaths. There isn't even a plan, other than to keep kidnapping children and blowing things up till everything "works out.")
In cult-like fashion, Jenny has been taught that the Underground leaders are higher than life figures, that they're like the characters in the Arthurian legends (except more perfect), like the Three Musketeers, or even quasi-godlike: "Stephen's been shot about sixty times, and he always gets back up," and they alone are the source of "hope" in the lives of the telepaths living with them - "every time we give up hope, they bring us more." The outside world is nothing but slavery and abuse - especially by the Corps - while with us, and only with us, can you have hope.
Jenny has been kept from ever seeing or hearing another side. Restricting access to information is easy when everyone's housed in hidden "safehouses" or underground bunkers with limited access to TV, radio, or the 'nets, and can only read the books you make available to them. Underground leaders tell their followers that if the Corps ever "captures" them, they will be sent to prison camps and tortured. They tell them that the Corps will dissect them. They tell them that the Corps is responsible for the oppression of telepaths, and that's why they have to kill Psi Cops. They tell them that, in Jenny's words, the Corps "makes people marry people they don't want to, because they breed people like they breed dogs to get poodles and things." (There are arranged marriages in the Corps, but no one is "bred like dogs.") They tell them that the Corps "steals babies, takes them off and raises them."
To a child like Jenny, her life on the outside was already so bad, anything would be an improvement - and the people who saved her from that life are almost godlike.
Jenny stayed at the "safehouse" while the rogue leadership went to Tennessee. Soon after, as she went to the store to shoplift booze - the rogues have taught her how to pass into a store undetected, using her telepathic abilities not to be seen, and she and some of the other kids regularly use this ability to shoplift booze - she was picked up by the Corps. (She had her diary on her at the time.) Perhaps it was random - they knew there was a "safehouse" in the area, and were keeping watch, hoping to bring into custody someone with information about the Underground's movements. They caught Jenny.
Realizing what they had, they laid a false trail to make it look like she really was picked up for shoplifting (again). There was a big raid in in the final stages of planning (three days away), and they didn't want the rogue leaders to catch on and change their plans. The plan worked - the rogue leaders thought Jenny was being held in the juvie system awaiting bail, and with everything else going on, they didn't think much of it - someone would have to to pretend to be a relative of hers, bail her out, and bring her back, but it would take time forge the documents. They would deal with it later.
The Corps, meanwhile, learned everything about Jenny's life, and more about the Underground's activities, both from the diary and from the deep scan that they subjected her to, but they erased her memory of the scan. The director himself read her diary.
Jenny's life story is just so sad all around, in every way, that the Corps authorities take pity on her. Jenny, now thirteen, has been the victim of everyone else's bad life decisions - her father, her mother, her abusers, the Underground leaders... everyone. And so they set out to turn her life around. She is given intense counseling, structure, authority, family. The director himself sympathizes with her, having lost his own (telepath) mother when he was only four years old. Jenny is an orphan, and he was, too - at last as much as Jenny is, since both of them had absentee fathers. Kevin's father was long gone by the time he was four.
Kevin had also been taken in by the Underground as a boy, when his mom died - but unlike Jenny, he had gotten out. He'd found another place to live. Gotten his GED. Gotten into college on full scholarship - a BS from ASU in neurophysics, a masters in the same from Harvard, then a law degree, graduating first in his class. He'd pulled his life together from absolutely nothing - and few could manage that. And for all the problems of his youth, he'd never been abused like Jenny had.
Jenny is sent to a Psi Corps school - but not immediately fully integrated into school life, because they fear she may become violent. The teachers and counselors have to address her self-destructive behaviors, like substance abuse, and self-harm. They have to slowly "de-program" her and show her that she's actually safe. They provide her with an education, with structure, and with emotional support, knowing that after what she's been through, the path to recovery won't be a straight line. It is a long road. They show her that there are other sources of "hope" in this life than the dead-end life the Underground was presenting her with, and though life in the Corps isn't perfect (because the normals' oppressive laws are what they are), she finally has a home.
It takes some time, but Jenny does pull herself together. Nothing more is known about her other than that she has a daughter, and that daughter is Talia's mother.