She used a disabled mobile phone to call emergency services on Sunday morning after sneaking out of a window at her parent’s house in California.

It was just after 6am and “in her mind, she was risking her life,” one police source told The Mirror.

The responding police officer thought she was a girl, 10-years-old at most. In fact, she is 17 and led him to the house where she and her 12 siblings had been held captive by their parents, starving, filthy and in “horrific” conditions.

David Allen Turpin, 57, and Louise Anna Turpin, 49, were arrested that morning and each charged with nine counts of torture and 10 counts of child endangerment. Police found the girl’s – woman’s – siblings starved and “shackled to their beds with chains and padlocks in dark and foul-smelling surroundings”.

“The victims appeared to be malnourished and very dirty,” the statement from the Riverside County Sheriff’s Office said, AAP reports.

Now, as the world is reeling from such a heinous and incomprehensible scene, a disturbing history of potential abuse is emerging. Insight from extended family and neighbours details the Turpin’s cult-like possessiveness over their children, and implies a pattern of abuse that will take years for these children to recover from.

But first, the 17-year-old girl and the conditions she survived.

The day of the rescue

“We do need to acknowledge the courage of the young girl who escaped from that residence to bring attention so they could get the help that they so needed,” Captain Greg Fellows of the Riverside County Sheriff’s Department told reporters at a Tuesday news conference, The Washington Post reports.

“If you can imagine being 17-years-old and appearing to be a 10-year-old, being chained to a bed, being malnourished and the injuries associated with that — I would call that torture.”

After being given food and water, the siblings – aged between two and 29 – were taken to hospital. The seven eldest siblings were still undergoing treatment at the time of Tuesday’s news conference and a spokesperson from the Department of Public Social Services said officials are seeking authorisation to provide care for the siblings – including the adults, if needed.

According to Fellows, the Turpin parents were “perplexed” when the police barged in on Sunday morning, and “unable to immediately provide a logical reason” why their children were chained up.

One neighbour, who chose to remain anonymous, told The Mirror Louise Turpin was “coughing and acting weird” when talking to police.

“The police officer kept talking and she kept just, like, smirking and, like, kinda, like, she spit twice down at the floor,” the neighbour reportedly said.

That "dirty, filthy" suburban home was also a school, police have confirmed.

Devoutly Christian, the Turpins homeschooled their children and, according to the Houston Chronicle, they listed it with the State Department of Education as the 'Sandcastle Day School'.

Six children were in attendance during the 2016-17 school year, all believed to be the couple's children.

"Shocked" family members speak out

Speaking to ABC News, David Turpin's parents, James and Betty Turpin of West Virginia, said their grandchildren were given "very strict homeschooling" and made to memorise long passages in the Bible. Some of the children attempted to memorise it in its entity.

James and Betty said they were "surprised and shocked" at the horrific news on Sunday. They said their son and daughter-in-law chose to have so many children because they believed "God called on them" to procreate. And confirmed they hadn't visited the family in five years.

LISTEN: As soon as she picked up a tennis racket, Jelena Dokic started being abused by her father... Post continues below.

Then, there is Louise's side of the family.

One of Louise's sisters, Elizabeth Jane Flores, 41, from Tennessee who has not seen Louise in 19 years, told Daily Mail she knew something "wasn't right" but never expected such an horrific outcome.

"We have been so worried about them because it's been so strange but there was nothing we could do. They wouldn't let anyone visit and we didn't know their address," she said. "I haven't seen her in 19 years. We would talk on the phone from time to time, but every time I would ask to talk to her kids, she wouldn't let me."

She said Louise's parents tried several times to visit their grandchildren, however were forced to turn around at the airport after Louise failed to provide her address.

"She never let us talk to her kids. She wouldn't even accept my Facebook request," Flores said. "My parents booked several flights to go see them but when they got there they wouldn't tell them where to go and my parents left crying every time. They died before they got to see them again."

Flores also told Good Morning America that when she was staying with her sister's family for a short time several years ago, David would watch her in the shower. She said she was terrified, but he acted like it was a "joke".

Looking back, she said she sees problems she didn't pick up on at the time. Through tears, she offered her support to the children.

"I want the kids to know that there’s people that love them and that there’s family that love them and I hope to be able to see the children," Flores said.

As well as this, a third sister, McCeary Lee, who lives on the Pacific island of Guam, reluctantly posted to Facebook asking for privacy.

"We knew David and Louise were a bit odd, but there was no way in hell we knew they were torturing our nieces and nephews," Lee posted on Facebook, News Corp reports. "They were extremely private people who rarely spoke to any of us and didn't even show up to my mother and father's funeral."

Neighbours describe eerie encounters

These reports of reclusion and possessiveness are echoed by the neighbours to the "horrific" house in California.

Robert Perkins, for example, said he complimented a handful of Turpin children on the nativity scene they were building in the front yard a couple of Christmases ago. "They didn't say a word" in response, he told News Corp.

Then, there is Wendy Martinez, who was walking by the house one night last October and saw four of the children turfing the garden while Louise watched on from the door. Again, no one responded to her "hello".

"They were very afraid," she told News Corp, referring to the children. "Like they had never seen people before."

On man who lived around the corner, Andrew Santillan, told Press Enterprise, he "had no idea this was going on" and that he "didn't even realise there were kids in the house".

Every account - the neighbours' and the sisters' and the grandparents' - adds another layer of creepiness until the whole scenario reeks of something sinister.

This is made even more so by the two houses the family left behind in Texas several years ago.

The homes they left behind in Texas

According to a former neighbour who now lives in the house the Turpins lived in before moving to California, the children "were never allowed to go outside and play".

"They homeschooled everyone of them and one day they just upped and left," the women who chose to remain anonymous told WFAA.

According to News Corp, it was unpaid medical bills and a house overflowing with junk that forced the Turpins out of Texas.

But a discovery in the closets of the main bedroom suggests the abuse and "torture" discovered on Sunday might have been going on for several years.

The same neighbour who observed the children were mostly kept indoors, found unusual openings in the master bedroom closet that appeared to work like air vents. She speculated they might have been used by the Turpins to keep the children locked up in the closet.

As well as this, the Anderson family who moved into an older house of the Turpins, also in Texas, 18 years ago said the conditions of the house were - that word again - horrific.

Speaking to The Mirror, the Andersons said the house's windows were smashed and boarded up; that the carpets and walls were covered in faeces; and that there were scratches on the backs of doors.

Again, considering Sunday's discovery, there's speculation the scratches were caused by children and not animals as originally thought.

Both Turpin parents are currently behind bars with bail set at $9 million each, however no criminal case has been filed, The Washington Post reports. Speaking to media on Tuesday, police said there is no evidence yet to point to sexual abuse but said the investigation is ongoing. Prosecutors will make a decision about the charges when the couple is arraigned on Thursday.

In the meantime, we can only hope those 13 siblings - who all appear like children, even though the eldest is 29 and seven are legally adults - are safe and recovering and, somehow, making their way forward from such an abysmal, meaningless, evil trauma.