I'd thought it was going to be a typical teen movie: soccer, school, a bit of romance. But when the footage came, we watched it with tears running down our faces. These children wanted the world to know what it was like to live with a parent with HIV/Aids, and the 14-minute film they have made shows their reality.

Four years before, we were starting a major Oxford University research study of children living in Aids-affected families, interviewing 6,000 families across South Africa. We asked 12 children to form our teen advisory group, and ever since the TAG team, as they call themselves, have shaped our research and our views.

Our findings have revealed that children are severely affected if their parents have HIV. We have visited the TAG team and met their families over the years and, despite our attempts to help, we have seen so many of our statistics play out in their lives too.

Children orphaned by HIV/Aids or with Aids-ill parents are twice as likely to suffer depression, anxiety and feel suicidal than other children, according to our research. More than a third miss school regularly to help with medical care and 37% go to bed hungry more than twice a week. The stress of poverty and HIV leads to three times more child abuse. We also found even more dangerous risks: girls with Aids-ill parents, living with abuse and in poverty, have a 57% chance of having sex in exchange for food, school fees or shelter.

The South African government, the Southern African Development Community, Unicef, USAid and Save the Children have used these findings to make evidence-based policies. Key services include social welfare grants to poor families and the growing rollout of anti-retroviral medication; when parental disability is reduced and food is available, Aids-affected children do much better. Free schooling improves children's school access and reduces girls' sexual risks.

But in today's context of shrinking budgets and rising numbers of Aids-affected children, many of these services are extremely hard to provide. The 'brain drain' has stripped southern Africa of social workers and medical staff, and there simply aren't enough staff to respond to the child abuse that is a major cause of risk. Many of the evidence-based programmes to prevent abuse and bullying are developed in the west, and have yet to be adapted and tested in low-resource countries.

And in every meeting with ministers, government officials and NGOs, the problem of Aids-related stigma remains a massive issue that we all want to resolve but don't quite know how.

So when they asked us if they could make a film, research staff donated cameras and our producer Caroline worked for almost nothing, making sound equipment with the kids out of tinfoil and cardboard. We changed the names but worried endlessly – was it ethical to show their emotions and lives to the world? The third time we went back to ask them how they felt they laughed at us – they wanted people to see this, to understand their lives, and that's why they made this.

But this gave us an idea. All these stories share a sense of being alone. Their parents are suffering from today's most stigmatised disease, and half of Aids-affected children in our research are teased, gossiped about, and isolated. This film gives a chance to show them – and other children in their situation – that people worldwide support them and wish them well.

Will this work? I don't know yet. But the TAG team have done their part. We are hoping to collect 5,000 messages of support to challenge the stigma experienced by children affected by Aids. To view the film online and show your support, please go to: Young Carers SA and leave them a message. You can also leave messages on our Facebook page. . The film will be launched at the International Aids conference, which starts in Washington DC on 22 July.

Lucie Cluver is a lecturer in evidence-based social intervention at Oxford University. She has spent the last decade studying the children of Aids victims in Africa, particularly looking at effects on mental and physical health. She is a trained social worker, and has practiced in South Africa and the UK

Guardian health editor Sarah Boseley will be at the Aids 2012 conference in Washington DC – you can follow her articles here and her Twitter feed @sarahboseley

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