A forthcoming book is revealing new details about the crimes of David and Louise Turpin, the California parents who tortured, shackled and starved their children, the New York Post reports.

As CrimeOnline previously reported, police arrested the couple in January 2018 after one of the kids escaped the family’s home and called 911 on a cellphone.

Inside the residence in Perris, California, investigators found evidence the Turpins had abused 12 of their 13 kids amid deplorable conditions. The couple later pleaded guilty to multiple counts of child abuse.

In “The Family Next Door,” author John Glatt traces the increasingly horrific treatment the parents inflicted on their kids and the warning signs that were missed.

The book reportedly claimed that David Turpin was making a six-figure salary as an engineer in the early 1990s, which allowed the couple to spend extravagantly. They paid to fly in family members for visits while residing in Texas, lived in a beautiful home and ate at expensive restaurants.

“We thought she had the perfect life,” Louise’s half brother, Billy Robinette Jr., said.

Yet cracks in the facade began to emerge. The couple reportedly filed for bankruptcy in 1992. When their daughter Jennifer started first grade, she was bullied by her peers. The girl was older than others in her class, she looked frail and had greasy hair with roughly cut bangs. She wore the same top every day and her peers complained of her smelling badly, according to the book.

And in 1995, it was revealed that Louise had a gambling problem.

“I was in shock,” Louise’s younger sister, Elizabeth, said in an interview with the author. “We were all raised up in a strict Christian home and taught that gambling was a sin.”

According to one account in the book, David and Louise went to a casino while on a long-distance trip. When they returned to the vehicle several hours later, David appeared angry that Louise wouldn’t stop when she was losing. He said he hoped they would have enough gas money to get home.

Louise then yelled, “I’m not a child! Stop bossing me around!”

Elizabeth recalled how strict David and Louise were with their children, who had to ask permission to even use the bathroom and eat. Elizabeth said while she lived with the family for a summer, she never saw David or Louise kiss or hold the kids.

For mealtimes, Louise would call each child one by one. Once the child was seated, he or she would have to wait for permission to begin eating, the sister claimed.

By 1997, when Jennifer started second grade, her hygiene had gotten worse. Classmate Jessica Bermejo said Jennifer “smelled just like dirty clothes and urine” and made disturbing comments in front of her peers.

“She was talking about things that could indicate sexual abuse,” Bermejo is quoted as saying. “Things that were inappropriate for that age.”

Jennifer would stop attending public school within the next couple of years. David had reportedly decided home school was best.

Around this time, in the late 1990s, Louise was regularly gambling and losing, and she reportedly told her sister in December 1998 that the couple would soon file for bankruptcy again. The bank was also foreclosing on their home.

When the Turpins moved out of their house, the new owners were so disgusted at the condition of the home that they took pictures. Grime was caked on the carpets and floors. Large stains, which appeared to be fecal matter, covered the walls of every room. The stench was unbearable.

In 1999, the family moved to Rio Vista, Texas, and David and Louise began turning violent.

“It started with slapping, hitting, throwing around the room,” Riverside County Deputy District Attorney Kevin Beecham reportedly said. “And it aggravated to belts.”

Riverside County District Attorney Mike Hestrin said none of the kids were allowed to shower more than once per year.

And despite David Turpin’s purported home schooling, Hestrin said some of the children lacked basic reading and writing skills.

The kids were also malnourished, so much so that their growth was stunted, inflicting permanent cognitive and physical harm, according to the book excerpt. Despite this, Louise would send photos of the kids to her family; the children always appeared well dressed and smiling.

“The pictures we got always looked like healthy kids,” Louise’s sister Teresa reportedly said. “They always had smiles. They were always dressed in the nicest of clothes.”

In 2004, the Turpins bought a new double-wide mobile home, which they all moved into, because their house was uninhabitable, with feces and garbage everywhere.

Soon after, David would build a cage to detain any children who broke the rules.

The couple later rented an apartment 40 miles away and abandoned most of the children, except for two babies, which they brought with them. Two teenagers — Jennifer and Joshua — were told to look after the younger siblings.

David would stop by every few days to deliver frozen food, but Louise never visited the other kids.

Joshua and Jennifer were reportedly forced to punish their younger brothers and sisters and lock them up.

Jennifer escaped one morning and sought help from a neighbor; she wanted to know how she could find an apartment, a job and a car. The neighbor brought Jennifer to town, but she had no identification and no social skills.

“So what did she do?” said Beecham, the deputy district attorney. “She called her mother. And her mother came, picked her up, and took her away.”

That incident alone should have raised red flags, Sheriff Rodney Watson said in an interview for the book.

“A lot of people will dismiss some things that they hear as just crazy talk, which is sad,” Watson. “We could have stopped a lot of years of suffering.”

By July 2010, the Turpins moved to Perris, California. David and Louise escalated the violence against their kids, using rope to tie them down and keep them in their rooms nearly all day.

In April 2019, David and Louise were sentenced to life in prison, although they could be eligible for parole in 25 years.

The Turpins earlier this year pleaded guilty to 14 criminal charges, including false imprisonment and torture. Twelve of their 13 children, some of whom were adults when the family was discovered in January 2018, were victimized. Authorities said the youngest child did not appear to have signs of abuse.