What happens when you feel responsible for an accidental death?

Georgina was just 15 months old and barely walking when she was hit and killed by a trailer. Photo / News.com.au

It was the split second that changed the lives of Emma and Peter Cockburn forever.

In April 2011, Peter arrived home from a building site in the town of Young in rural New South Wales, and was reversing his work trailer into the garage when he heard a sound.

"I felt a bump and instantly realised it didn't feel right," Mr Cockburn explained during his appearance on Insight , which will appear on SBS on Tuesday night.

"I ran behind the car and I seen my little girl laying on the ground and my worst nightmare had come true.

"Just seeing her there, my life just changed in that moment ... I didn't see her, and I went straight over her."

Mr Cockburn had accidentally reversed over their 15 month old daughter, Georgina, and despite desperate efforts, their little girl couldn't be saved.

"She crawled her way into that garage," Mr Cockburn explained.

"My wife Emma was out mowing the lawn at the time, and I just ran straight out to her yelling 'I ran over Georgie, I ran over Georgie', screaming at her to come and help me."

Mrs Cockburn, who had only checked on their four children 10 minutes before the accident occurred, said she tried desperately to save their little girl.

"I ran in and there she is on the floor," Mrs Cockburn explained of the scene.

"I hit the floor, hit the concrete on my knees. I looked at her then looked away because I didn't want to see all the blood.

"I checked the back of her head because I thought the back of her head was cut because of how much [blood] there was. But it was all coming from her little face.

"I went in to automatic mode having done years of CPR training as a teacher, and we are just doing CPR and waiting for the ambulance to come which seemed to take forever.

"It was only 10 minutes but it felt like a lifetime."

Mr Cockburn said he felt numb, knowing there was no chance his youngest daughter could've survived the impact of his trailer. But he held hope.

"It's a dream that you don't wake up in," he said. "It's a nightmare.

"You do whatever you can to try and get the life back in to her [and] breathing again. But deep down we knew. We both knew."

Georgina Cockburn. Photo / News.com.au

Georgina, who was the Cockburn's youngest daughter, was described as a happy toddler who loved playing with her sisters and dancing to The Wiggles.

Following the impact, she was rushed to hospital where Mr and Mrs Cockburn were given the tragic news that their daughter hadn't survived the hit.

"The doctor came in and said 'all we can do is make her comfortable'," Mrs Cockburn recalled.

"In other words, she's gone and there's nothing we can do."

Mr Cockburn said they were in "disbelief" and only wish they'd acted on a warning sign that had occurred three months prior to Georgie's death.

"The most gut-wrenching thing for us is that we had a near miss three months before," Mr Cockburn explained.

"I was at home and [Georgie] was in the garage when Emma drove in.

"She gave us that warning and it didn't twig. That's the biggest thing that gets us still ... We had a warning. We had an opportunity to make a difference and prevent what did happen."

Sadly, deaths involving reversing cars are not uncommon in Australia. Kidsafe statistics reveal an average of seven children under the age of 14 die in driveway accidents in Australia every year.

Peter and Emma Cockburn hope to raise awareness about driveway safety. Photo / News.com.au

And while tragedies like this can crush the most solid of marriages — the Cockburns made a pact there would be no blame or recriminations.

"People found it hard to talk to us, they didn't know what to say," Mr Cockburn said.

"For the first two weeks [following the accident] ... we had a house full of people. We were very blessed with a wonderful network of family and friends ... which in hindsight was the best possible thing.

"At the hospital, I sat with Emma and we had Georgie in our arms. I said to her can we make a pact that we don't blame each other.

"That it's happened and we can't change it and we need to move forward for our kids."

Mr Cockburn said they still don't know exactly how their 15-month old daughter managed to get out of their house and in to the garage, and despite being called a "murderer" by a stranger — they hope to use their experience as a warning to other parents.

"At the end of the day we've done something out of the ordinary by ending someone's life," he said.

"That is something that is going to stick with you and you are always going to have that blame.

"Kids are too impulsive and they are not going to think twice," Mrs Cockburn added.

"So we have to think for them especially when they are little."