In 2008 the raw, observational ABC documentary The Oasis spotlighted the unruly lives of a group of vulnerable teens living in an inner-city Sydney youth refuge – and in doing so sparked a nationwide conversation around youth homelessness.

Directed by Ian Darling and Sascha Ettinger-Epstein, the film brought with it a notable political and social impact: it led to a live televised forum hosted by Tony Jones and sparked media coverage from major network stations, with the DVD distributed to every high school in Australia. Perhaps most significantly it caught the attention of federal parliament.

“It felt like a really optimistic time,” director Ettinger-Epstein says, recalling the Rudd government’s commitment to halving homelessness by 2020, and the landmark white paper on youth homelessness, The Road Home.

“At the time there was such a groundswell of goodwill towards the issue and we thought something really was going to happen. But once something else gets a bit of traction, [homelessness] gets bumped off the agenda. This was a crying shame.”

One year shy of 2020 and the statistics for those living without stable housing hasn’t come close to halving. In fact, social inequality has only worsened, with the number of people experiencing homelessness jumping 14% to 116,000 between the Census years of 2011 and 2016. And youth homelessness has increased disproportionately, with approximately 40,000 people under 25 homeless every night.

For Ettinger-Epstein and Darling, these bleak figures – and the lack of political action around the issue – was the catalyst for their follow-up documentary, Life After the Oasis. Once again putting faces to the statistics, the sequel presents a candid portrait of how its original teenage subjects have spent the past decade.

The documentary returns to a few familiar faces – most no longer homeless, though one of them, Hayley (one of the most charismatic personalities of the first film), is found still living on the streets of Melbourne. The others have made steady recovery journeys: Darren, last seen battling mental health issues and a drug addiction, is now several months sober and living in his own unit; Emma has since split up with her partner, Trent, and is now raising her children as a single mum; Owen, one of the most troubled teenagers in the original film, is working with the Salvation Army and pursuing his passion for music; and Chris, who was abused by his father as a child, has reconnected with his estranged mother.

Ettinger-Epstein says she was deeply moved by the strength of the participants. “I was astounded that [some of them] came out the other side … and really happy that they are genuinely making a quality of life for themselves.”

Cutting between flashbacks and the present day, the sequel – which premieres this week at Sydney film festival – is less gritty and chaotic than its predecessor. Its mood echoes the more mellow, lucid reflections of its now-adult subjects as they contemplate how far they’ve come, and revisit locations from the original film – including the Salvation Army’s Sydney Oasis Youth Support Network, previously run by Major Paul and Captain Robbin Moulds.

Nowadays the husband and wife team work with asylum seekers and refugees in Sydney’s western suburbs – but for 13 years, they played an integral role in reshaping the lives of many children who entered the centre, offering a personal, empathetic approach alongside critical intervention support services.

Darren calls Paul Moulds a “father figure”, whose generosity and compassion went beyond his job title. “He took the time to get to know us and took time out of his own life. If it wasn’t for the Oasis, I don’t think I would be alive right now,” he tells the Guardian.

There is no single reason why these young people were once on the streets. The complexities of their backgrounds vary from childhood trauma and abuse to mental health issues to family violence and neglect.

Chris describes the experience of watching the original documentary as “numbing”, but thinks it helped him identify what he wanted to change in himself.

“I was quite surprised by the whole picture of it,” he says. “I didn’t understand what actual [homelessness] was until watching that … [I didn’t understand] what made me homeless. Because you can end up homeless from many things.”

He hopes his appearance in both documentaries will provide audiences with an illuminating and more empathetic attitude towards homeless youth.

“I wanted to show that I’m a normal person. Everyone’s got their own problems. I wanted to show that anyone could end up here … and that if you gave some of us a chance, some of us would do good in our lives.”

Ettinger-Epstein hopes the documentary will reignite public interest in the issue of youth homelessness. “The stories illustrated the failure of policy and where society was heading,” she says. “We are hoping to make people care again, show people that over time change can happen and that their lives can go somewhere.”

• Life After the Oasis premieres at Sydney film festival on 13 June