Nicola Sallese was last seen in 2008 driving his car down a road in Sheffield, in Tasmania's north-west.
Neither his car nor body have ever been found and a funeral has not been held.
"My brother and I have been encouraged to have a memorial for now, but we haven't even wanted to do that," his son Jason Sallese said.
"We thought once we find him we will do a funeral and we will do it once."
It is hoped new sonar technology and the help of a YouTuber will lead to the discovery of Mr Sallese's car somewhere in a Tasmanian waterway.
"When my Dad went missing this sort of technology wasn't available," he said.
A social man
Nicola Sallese migrated to Australia from Italy in 1961 when he was 21, following his brother to Tasmania.
He worked all over the state for the Hydro Electric Commission, a job he held for almost 40 years.
"He still had a very strong Italian accent," Mr Sallese said.
"When he first came here he didn't know any English at all."
The 69-year-old was closely connected to the Sheffield Bowls Club, competing weekly and spent time training and socialising at the club.
"He was very social," he said.
Around the time of his disappearance, he had just been diagnosed with dementia.
His wife Jill died in 2000 and he lived alone on a large property.
"We were in the process of getting him medication and his house was put on the market so he could go into a smaller house," Mr Sallese said.
"He used to get a bit muddled with the days of the week and my brother would help him out with that, like tell him he had to go to bowls.
Despite that, he was still a very independent man.
A mystery drive
Ten years ago a coroner found Nicola Sallese died on or around November 17, 2008.
The coroner could not make any findings on the cause of his death or his whereabouts but said the circumstances were not suspicious.
Jason Sallese said while the family accepts the report, they still want to find their father.
He has no idea where his father was driving to and has tried to think of all the scenarios including a drive to southern Tasmania.
"Around the time he went missing it was my eldest daughter's first birthday," he said.
"The following weekend he was meant to come down with my brother and sister-in-law to my place for her birthday, so we don't know if he's woken up one day and thought 'I've got to go'.
"I wish we knew."
'This could be it'
Mr Sallese has just wrapped up a five-day search in Tasmania's south using a diver with sonar technology.
The search covered Southport to Hastings after a sighting.
"It's a sighting we've had for a while but have never had the opportunity to check," he said.
"We are checking all the waterways and we've cleared up to Huonville."
Southport is a four-and-a-half-hour drive from Sheffield, but Mr Sallese said his father would have been capable of a long drive.
The search included the help of a diver, known as "Diver Dan", who is affiliated with American YouTube channel Adventures With Purpose that helps families of missing people by searching waterways.
The group started off as volunteers diving for rubbish but soon began uncovering clues to missing person cases and has a strong online presence.
The recent search in southern Tasmania located four cars in rivers, but none of them were Nicola's.
It also found guns and knives, which have been reported to Tasmania Police.
During a search near Franklin, the team thought they were close to finding him.
"We'd earmarked this place as a very high potential spot for a car to be because there's no railing or anything and it's right next to the river," Mr Sallese said.
"You can't get excited because I'm guessing there's lots of cars in the water that we don't know about.
"But at that very moment, I thought, 'This could be it'," he said.
The next search
Mr Sallese said the search will now concentrate on dams and lakes near where Nicola used to work with the Hydro.
"If I had the funds I would cover the whole state," Mr Sallese said.
The diver, from Sydney, covered the costs of his trip to Tasmania, spending $2,500 to come down with his search boat.
Funds are tight, and he slept in a swag.
"We are trying to raise money to cover the week he was just down here," Mr Sallese said.
When he doesn't have access to the sonar technology, Mr Sallese investigates tip-offs himself or finds people who are willing to help, like when a car was spotted in Lake Barrington on the north-west.
"I put it on Facebook and before I knew it I had people willing to go down and have a look," he said.
Mr Sallese runs the page Help Find Nicola Sallese, which has almost 7,000 followers.
'If we find the car, we find dad'
While his father's disappearance is still an open police file, the family don't get much assistance with searches.
They are still on the look out for a Toyota Camry 2006 model with registration number FH2973.
"We feel like if we find the car, we will find dad as well," Mr Sallese said.
He said the whole family have been involved in trying to find him.
"Over the years our group has grown," he said.
"It doesn't take over your whole world, but it sort of does.
"It's a big part of what goes on and it takes up a lot of time.
Anyone with information can contact Tasmania Police on 131 444 or make contact with Jason Sallese through the Help Find Nicola Sallese page.
