A father who lost his three children. And the man who killed them.Samuel Davidson was three times over the legal alcohol limit, drug-affected and out of control when the ute he was driving mounted a footpath and mowed down seven children in the 2020 Oatlands tragedy that shocked the nation. 

Abdallah siblings Antony (13), Angelina (12), and Sienna (8), along with their cousin Veronique Sakr (11), were all killed instantly. Three other children were injured. 

Davidson was sentenced on appeal to 20 years in prison, with a non-parole period of 15 years. 

At the time, many Australians couldn't comprehend how parents Danny and Leila Abdallah publicly forgave him. But now, in an extraordinary act, Danny Abdallah's forgiveness reaches even deeper. 

Five years on from the tragedy, 7NEWS Spotlight has been granted rare access inside one of the country's harshest prisons to capture the raw and emotional encounter between a grieving father and the man who destroyed his world. It is an extraordinary television interview that challenges everything we think we know about restorative justice, remorse and forgiveness. 

For the first time, Australians will also hear from Davidson about that horrific day, including new revelations about the reasons behind his actions and the devastating consequences that followed. 

7NEWS Spotlight'sMichael Usher, who has followed the Abdallahs' story since the beginning, said: "For the past eight months, 7NEWS Spotlight has worked closely with Corrective Services NSW, lawyers and psychologists to make this possible. 

"We spent a week inside one of Australia's hardest prisons where TV cameras are rarely allowed to speak with a high-risk, high-security inmate serving one of the longest sentences for his crime. 

"Danny's journey to forgiveness has been long, complicated, and deeply emotional," he said. "What I witnessed inside those walls is something I never expected to see, and certainly never thought we'd be able to share with the Australian public." 

Where does justice end and mercy begin? And can forgiveness ever truly heal?

7News Spotlight uncovers the inside story of Australia's largest-ever superannuation disaster – the collapse of the First Guardian and Shield Master Funds.

More than 12,000 Australians' super balances wiped, and their futures stolen, with losses totalling over $1 billion and a government regulator that may have been asleep on the job.

Michael Usher speaks to several victims left without a cent to retire on, and an insider who allegedly helped sell them the dream.

Financial adviser Ferras Merhi, who has been banned from travelling and has had his assets frozen by ASIC, told 7News Spotlight: "I don't [sleep], it's hard. It kills me every day that in one shape or form, I've been involved either directly or indirectly in support of this particular product."

Michael Usher said: "Thousands of Aussie investors were conned by these very sophisticated schemes. They did their own research, but they were duped, because at every level, these schemes appeared to be checked and verified by reputable advisers and regulators, who we're meant to trust with our future.

"Australia should be outraged at this billion-dollar theft, which needs to be investigated at the highest levels. To lose every cent of your hard-earned retirement savings is beyond heartbreaking – it has ruined the lives of hard-working Australians."

Also this Sunday, guest reporter Sonia Kruger sits down with Melanie C, in London.

The former Spice Girl and The Voice coach opens up on the comment that nearly broke her and how she almost missed out on the gig of a lifetime.

She also shares how her daughter helped her reconnect with music, and the global movement that made her a household name.