For two years, the Turpin siblings planned their escape: New details about their life emerge.

The world is waiting for the parents who allegedly starved, tortured and abused their 13 children to face court today, five days after their 17-year-old daughter escaped through a window and called police on Sunday morning.

In a press conference held before the hearing, the Riverside County District Attorney Mike Hestrin laid out the charges against David Turpin, 57, and Louise Turpin, 49 who they say kept their children locked in doors, chained to beds, and only allowed them to shower once a year.

They are charged with 13 counts of torture; one lewd act on a child; seven counts of abuse of a dependent adult; six counts of child abuse; and 12 counts of false imprisonment.

The couple has pleaded not guilty. Hestrin said more charges will be added if further evidence comes to light and, as it stands, the Turpins are facing 94 years to life in prison for their alleged crimes.

Hestrin looked grim as he detailed the extent of the couple’s alleged abuse. Their children range in age between two and 29, however all are extremely malnourished and facing severe health problems because of the torture they suffered. The 17-year-old who called for help, for example, was presumed to be 10 years old by the responding police officers.

“The abuse and neglect intensified over time,” Hestrin said, WVNS 59News reports. He added the mistreatment worsened after the family moved to California from their former home in Texas.

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“All the victims were and are severely malnourished – to the point of muscle deterioration. Several of the victims have cognitive impairment and neuropathy, which is nerve damage as a result of extreme and negative abuse.”

The 29-year-old female victim currently weights 37kg, Hestrin said. He continued:

“None of the victims were allowed to shower more than once a year. One of the reasons for the punishments they suffered – being chained to a bed, beaten and strangled – was if the children were found to wash their hands above the wrist area. Then, they were accused of “playing in the water” and they would be chained up.”

“If convicted of all of these charges as currently filed, these defendants are facing up to 94 years to life in prison,” Riverside County District Attorney Michael Hestrin says, outlining charges against David and Louise Turpin https://t.co/uIuXMbpPjN pic.twitter.com/0n9sgIPZvG

— CBS News (@CBSNews) January 18, 2018

Alongside the direct abuse and torture, Hestrin said there were psychological taunts to keep the children desperate. They weren’t allowed to play with toys, for example, but the house was littered with many toys in their original packaging and unopened.

The same was seen with food:

“When they were not chained up, they were locked in different rooms and fed very little on a schedule,” Hestrin said. “The parents would apparently buy food for themselves and not allow the children to eat it. They would buy pies – apple pies, pumpkin pies – and leave them out on the counter. Letting the children look at the food but not eat it.”

Officers raided the house in the small city of Perris, about 113 km east of Los Angeles, on Sunday after the 17-year-old, whose name was not released, called the 911 emergency number.

Hestrin said the teenager had spent two years planning the escape with her siblings. When she eventually fled the house, one of her siblings joined her but became too frightened and went back home.

Hestrin said that to avoid being caught, the parents made their children sleep all day and stay awake all night, often going to bed between 4-5am.

The siblings hadn't seen a doctor in four years, and they had never seen a dentist. Authorities say they did not know what medication was. Some, also, did not even know what a police officer was.

On Wednesday afternoon, several investigators, some wearing black gloves, went in and out of the house, frequently carrying boxes and bags of material they placed in waiting vehicles. "The whole house is a crime scene," Riverside Sheriff's Deputy Mike Vasquez told AAP.

The most resounding question surrounding the case is why? Except for the single charge against David Turpin of a "lewd act against a minor", none of the charges appear sexually motivated.

What purpose did these two parents, who claimed to be Christians, have to deprive their children so horrifically?

Hestrin didn't have an answer, but he did say this: "I will tell you that as a prosecutor there are cases that stick with you and haunt you. Sometimes in this business, we are faced with looking at human depravity and that is what we are looking at here."

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