POLICE have charged Ella Tromp with stealing a car in the latest twist in the family saga that's gripped Australia.

Victoria police confirmed two charges have been laid, after inquiries from news.com.au.

A spokeswoman said a 22-year-old Silvan woman was charged with theft of a motor vehicle and possessing the proceeds of a crime [the car] on August 30 in Victoria. She was bailed to appear at Ringwood Magistrates Court on April 19, 2017.

Her sister Riana was also charged with theft of motor vehicle, but the charge has since been dismissed under section 33 of the Mental Health Act of NSW.

No other charges were expected against any other family member, police said, despite time and resources in two states being spent hunting for the family.

Speculation over whether the Tromp sisters were going to be charged has been increasing since it emerged the two had allegedly taken the car after they fled their parents at the Jenolan Caves, increasingly concerned by their erratic behaviour.

When asked how Ella and Riana left Jenolan Caves, police said they did so in a car they neither hired nor owned.

Riana separated from her sister and was then found in a catatonic state, hiding in the back of a local man's ute in Goulburn.

THE UNANSWERED QUESTIONS

Mark Tromp — who disappeared with wife Jacoba and children Mitchell, Ella and Riana — was the last of the family to be found on Saturday, after his wife turned up in Yass on Thursday.

He is alive and well, physically at least, but the mystery is far from over. We are left with almost as many questions as answers.

Where was Mark for the five days he was missing, when it seemed the whole country was searching for him?

Jacoba turned up on Thursday and was admitted to hospital, dazed and agitated. From there she was transferred to a Goulburn mental health facility. But where had she been from the moment she left her husband, on the Tuesday, until she arrived in Yass two days later? And how did she get to Yass?

The mental health issues that have plagued the family have been a source of confusion as well. How could more than one person in the same family have such serious delusions — all at the same time? Why were they all so convinced someone was out to get them? What led to the family meltdown?

Police say they had no debts and no one was chasing them.

Two of the couple's children, Mitchell and Ella, told reporters yesterday that they couldn't explain what happened. But have they said everything they know?

Perhaps most bizarre is the fact that the Tromps' children Mitchell and Ella seem as much in the dark about what went wrong as the rest of Australia.

Speaking to the media yesterday, they shared few clues about the ordeal — even though they were there for part of it — and admitted the whole five-day mystery was "hard to explain".

Both said they were "still confused" about the trip.

"I had to go with the family because I wanted to see where they were going," Mitchell said.

"I couldn't leave them. But, yeah, it was tough to see your family like that and I've never seen anyone like it."

Asked what triggered the trip, Ella said: "It is very confusing, I still feel confused … I think our state of minds wasn't in the best place and … there's no one reason for it. It's bizarre."

The siblings were reluctant to expand further on details saying "police are still investigating".

In an earlier public appeal for assistance when Mark was still missing, the kids expressed how much they loved their missing dad.

"He's not dangerous, he's my mate, my father. I love him," Mitchell told reporters.

Pressure had apparently been building on the usually happy family in the days before they fled their Silvan home — a lush and sprawling berry farm where visitors are welcomed to pick redcurrant berries and explore the idyllic livestock-studded surrounds.

Mitch said his father had become "paranoid" after a "build-up of different, normal everyday events" leading him and Jacoba to unravel and take the rest of the family with them.

"I've never seen anything like it," Mitch said.

"It's really hard to explain or put a word on it but they were just fearing for their lives and then they decided to flee".

Mitch said the "pressure", as he described it, "slowly got worse as the days went by".

He's tried to explain his father's disappearance saying he "thinks people are after him. He's not in a good state of mind".