Tromp family: The mystery of a tech-free road trip gone wrong

A family of five who disappeared on a tech-free road-trip, turning up one by one after a week-long odyssey of more than 1,600km (995 miles) which ended with a police investigation and two family members in psychiatric care. This was a missing person mystery that held Australia spellbound, writes Trevor Marshallsea.

The Tromp family were by all accounts a normal, hard-working household.

Mark Tromp, 51, and wife Jacoba, 53, had established a successful redcurrant farm and earth-moving business at their property in Silvan, on the outskirts of the Victorian capital, Melbourne.

But with little warning, on Monday 29 August they and their three adult children - Riana, 29, Mitchell, 25, and Ella 22 - got into a car and headed north.

They didn't just leave their family farm, they had fled.

Police, later called to the home to investigate, found passports, credit cards and mobile phones had been left behind. This was to be a cash-only, "off the grid" road trip, with no way of being followed.

It was later revealed Mark and Jacoba had been suffering increasing signs of stress and paranoia. According to media reports, at least one of them had become convinced someone was out to kill them, and take their money.

The only phone not left behind belonged to Mitchell. He appeared to be the only one in the family not swept up in the belief that they were in danger.

He later said he had gone along to ensure they would all be safe, but that his parents became increasingly delusional and hard to tolerate.

Some 30km away from home, they made him throw his phone out of the car window. They were apparently convinced it was being used to track them.

A stolen car and a 'catatonic' stowaway

The family drove, in Ella's silver Peugeot SUV, through that first day and night until reaching the New South Wales town of Bathurst, 800km away, to the west of Sydney. It was there at 07:00 on Tuesday that Mitchell left the family.

And then there were four

Later on Tuesday morning, the remaining four Tromps headed east from Bathurst to a popular tourist spot, the Jenolan Caves. It was there that Riana and Ella decided to also part from their parents. They did this by stealing a car.

The two sisters drove south to the town of Goulburn, where they reported their parents had gone missing.

The story made its way into the media and a bemused Australian public wondered how a family could have become so strangely separated, and separately lost, on what was at first thought to have been a driving holiday - and in their own country. This was not remote territory, not the vast Australian outback. At all times they were close to large towns.

In Goulburn, Riana and Ella decided to part ways at a petrol station, with Ella saying she wanted to go home to feed her horses. She became the first Tromp to be located when she arrived back at the family farm on Tuesday night and found police there. Mitchell would arrive home the following morning, having taken a series of trains.

And then there were three

While Mitchell and Ella appeared reasonably unaffected mentally, the same could not be said of Riana.

She had climbed into the back of a utility vehicle in Goulburn, and was only discovered there by the male driver after he had driven almost an hour away. He pulled over and found Riana to be in what he called a catatonic state, saying she did not know her name, nor where she was.