For 27 years Victoria Donda believed that her name was AnalÍa, that she was born on a patch of wasteland in Buenos Aires and brought up by two loving parents. Three years ago she was told the awful truth: she was born in a secret torture centre run by the brutal junta that governed Argentina for seven years, she was ripped from her mother’s arms when she was 15 days old, and – most heartbreaking of all – the people she thought were her family were part of a regime responsible for the political abduction and murder of her real parents.

The truth was hard to take. “It was very hard, really horrible,” Victoria says. “Imagine if someone told you right now that your parents are not your parents.” She has a complex relationship with the couple who brought her up, a naval officer and his wife, whom she now calls her “appropriators”. The woman came from a poor background and was illiterate: “I taught her to read. She thought she was doing the right thing.” But she finds it difficult to talk about her “father” and refuses to mention his name. Juan Anto-nio Azic shot himself in the head in 2003 as he was about to be charged with child abduction and torturing prisoners. He survived, emerged from a coma and is now in a secure psychiatric unit awaiting trial.

“I’m his daughter: society can’t ask me to judge him,” Victoria says. “They raised me with love, and I love him still. He was responsible and he is in prison and I go to see him. He knows I think he needs to be under arrest. But I think love is not tied to whether you were responsible politically or not. Love works in a different way. If your child ends up being a serial killer, you don’t stop loving him. He will be imprisoned but you will keep on loving him. It’s the same thing.”

Victoria’s case is tragic, but it is far from unique. Between 1976 and 1983, human rights organisations estimate that between 10,000 and 30,000 people disappeared during the Dirty War, the junta’s attempt to “cleanse” Argentina of left-wing opponents. They won’t be coming back: witnesses from that time tell how prisoners were injected with paralysing drugs, stripped naked, crammed on to planes and dropped into the Rio de la Plata, so wide that you cannot see from one shore to the other. But what of their children – either abducted with their parents, or, like Victoria, born in one of those hell-hole detention centres?

The junta stole as many as 500 babies and gave them away to be raised by families with conservative values, military officers and political sympathisers. Now, as the nation continues trying to heal the wounds of a shameful period in its history, there is a growing will to restore to those children – now adults – their true identities.

At the forefront of the campaign, as they have been for 30 years, are the Mothers and the Grandmothers, of the Plaza de Mayo – named after the public square in Buenos Aires where they donned white headscarves and marched in front of the presidential palace to demand the return of their “disappeared” sons and daughters. Their vice-president, 88-year-old Rosa Roisinblit, has an imposing voice and nononsense manner forged by three decades of haranguing recalcitrant officials.

Rosa’s daughter was eight months pregnant when she disappeared in October 1978. “I was very disorientated,” Rosa says. “I didn’t know what to do. The only thing I could think was that they had to return my daughter soon because she was pregnant and needed to come home to have her baby. I was very naive.”

She joined other mothers she found at police stations around Buenos Aires, all desperate for information about their missing children. As years went by, it became clear that those children would never reappear, but the women would not rest until they found their grandchildren.

During the dictatorship the Grandmothers began to follow up reports of mothers who appeared suddenly with babies, despite never having been pregnant. The old ladies would make discreet inquiries, approaching the children or their friends, trying to find out more. They had a few successes as democracy returned to Argentina in 1983, and a year later came a scientific breakthrough: a test that could show if a child was part of a family despite the absence of the parents’ DNA.

In 2000, with the help of that test and an anonymous tip-off, Rosa found her grandchild. “It was a privilege,” she says. “He is a handsome boy, tall. To look at him, I have to crane my neck. He is lovely. At the beginning, it was so idyllic. But when his appropriators were put in jail, he changed completely. They stole him, and stealing a child is a crime. But they made him feel guilty. ‘We raised you, we fed you, took care of you when you were ill,’ they say. And he feels obliged to that family.”

Little by little, Rosa tried to win over her grandson. “He knew I was his grandmother, but he resisted a lot. When I called, he would say, ‘Don’t call me any more’. I said to him: ‘Tell me something: this woman who you call Mum, is she my daughter?’ Because he knows I am his grandmother. He clicked. And from then on, things began to change. He realised, you cannot turn the page. I am his real grandmother. He had another mother, and he knows who she was. And that woman is nothing more than a stranger who raised him. Our friendship began to grow. I began to win my grandson’s affection. Because after 22 years of looking for him, I had to win his affection. Today, I can say that the relationship with my grandson is good. He is married, soon he will be a father. And I am going to be a great-grandmother.”

For the first time, the Grandmothers’ campaign now has government support: President Néstor Kirchner is the first Argentine leader to make human rights trials a priority, and has sponsored a law to pay the children compensation. Nevertheless, the area is a legal and moral minefield. What if “recovered grandchildren” don’t want to be recovered? What if they are perfectly happy with the lives they have, and are unwilling to take a blood test that would prove that they are not who they think they are? One girl, Evelyn Vázquez, spent years fighting efforts to get a sample of her blood. In 2003, a court ruled in her favour, saying that “if she does not wish to know her true identity, the State cannot compel her to”.

Gabriel Cavallo, a federal judge who has worked on several such cases, says: “There is a whole debate, not yet resolved, about the ability of judges to investigate over and above the will of the person involved. Don’t forget that these minors are today adults. It’s not the same as it was before.”

In 1999 Cavallo ruled on the case of Claudia Poblete, 21, whose “father” had been a member of the military snatch squad that seized her real parents, and whom Cavallo ordered to be arrested. He says: “It was a huge surprise for her and very painful for me to have to tell her. The biological relatives were waiting outside the courtroom. She didn’t want to meet them. And then, over time, she started to adapt to her uncles and her grandmother. Today she has a relationship with both families.

“I was very conflicted about the whole thing. The truth is that many times, I wondered if I had the right to do such a thing. I even went into therapy myself.

“I felt sorry for having placed more conflict in this girl’s life than she already had. But I would respond to that by believing that, as far as I was able, I reunited her with the truth. I know it’s painful for her, but the truth is always more important than the lie. So beyond how it affects her psychologically, I think it is going to be a crucial point in her development and feel confident that she will move beyond it.”

And what of the babies adopted in good faith by families unconnected with the junta, who had no idea that their new child’s real parents had been murdered? One such is Tatiana Sfiligoy, the first child recovered by the Grandmothers in 1980, and now a psychologist who works with children of the disappeared.

She says the process of coming to terms with what happens can take many months or years. “Generally, the girl or boy knows that person as mother and father, and it’s very hard for them to erase those years from their heads. Of course, a crime has been committed here. But what one thinks is one thing, and what one feels is another. Just as I couldn’t erase what happened to me, the kids lived through things with their appropriators that they can’t simply forget. There is no button to erase the past.”

Tatiana, Victoria and others who have recovered their identities are strongly in favour of compelling people to give their DNA. “If I am being raped and a policeman is passing by, he has to intervene — he doesn’t ask whether I want him to,” Victoria says. In her case, finding out her true identity has made sense of many aspects of her life.

“I always liked strange combinations, like toffee and salami or chocolate and cheese. My mum was the same. I use very high heels all the time, and my mum never stepped down from hers. In all those things I’m very like my mother.” And since the age of 16, more than a decade before she began to question her identity, Victoria has been politically active in left-wing causes.

She began to work in the shanty towns that surround Buenos Aires, the very work that brought her parents to the attention of the military authorities in the 1970s. “The military had the notion that children should not grow up in the homes that had raised the subversives,” she says. “They had to take you to other ‘good’ homes that would not turn you into a subversive. In my case, they put me in with a Navy family and I still became a subversive. It didn’t work.”

The slums where Victoria worked are among Argentina’s worst, set in the shadow of a sprawling petrochemical complex. Half the children there have lead or other toxins in their blood; there is no sewerage or running water. With more than a touch of irony, inhabitants have called their shanty-towns Danubio Azul (Blue Danube) and Villa Inflamable (Inflammable Town).

Last month Victoria was elected to congress, the youngest woman to hold the office. In the slums where she built her reputation as a political activist, they are enormously proud of her. As we walk in through muddy streets, a little boy called Pipi runs up to Victoria with a broad grin: “I saw you on the telly!” he shouts happily. A group of women gather around Victoria like a homecoming queen. “We are so proud of her,” says Betina, one of the women who helps to run the soup kitchen. “It’s historic. Imagine, a colleague of ours — a national congresswoman!” One man wants to thank Victoria for helping him to find a job. “Now you’re a congresswoman, we’ll be bothering you all the time!” he says. “I’ll be changing my number,” she deadpans. “You’ll be changing your identity again,” another woman jokes. “I think I’ve got enough names for now,” Victoria replies. “And you keep calling me Analía.”

On a hot, cloudy day this month, President Kirchner unveiled a monument to the victims of state terrorism, a giant granite wall listing the names of the disappeared that zig-zags towards the river. Standing on a platform next to his wife Cristina, who will succeed him as president next month, the President addressed the families of those who disappeared. Many held grainy black-and-white photos of their missing relatives, listening to the President and watching his wife flutter at herself with a violet fan.

I spot Victoria amid the crowd, dressed in a bright red dress and her trademark high heels. She looks in her element, beaming at people who come to congratulate her on her election to congress. Many grandchildren compare finding their real identity to being born again, an event that radically changes the way they feel about themselves and the world, but Victoria doesn’t agree. “I have a new name and a new family, but I don’t have a new life,” she says. “I don’t think identity is like a pill you swallow. You build your identity with the decisions you take.

“What did change is that, before, I used to do my political work as a way to rebel against my family, whereas now I see it as continuing the work of my mother and father. I do it with much more responsibility than before.” As she walks along the memorial looking at the names, Victoria meets Lila Pastoriza, a woman who was with her mother in the torture centre: of the 5,000 who passed through it, Lily is one of only 200 to survive, and she was there when Victoria was born. They chat, and for a moment Victoria seems to lose her composure.

Later, Lily tells me: “We would speak a lot about what happened in there, what we knew, what we didn’t. Cori, Victoria’s mother, was pregnant, but obviously we didn’t know at the time what happened to the children. We even thought that Cori could be alive.”

Then she looks at me and says: “You know, Victoria asked me when her birthday was. She doesn’t know when she was born.”

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