Police in Perris, California, were shocked in mid-January to discover the 13 children of David and Louise Turpin had apparently been living in a house of horrors: Allegedly kept malnourished from lack of food and regularly abused, nearly all of the kids had also been imprisoned and tortured in the home, authorities believe.
Only the youngest child, it seems, was somewhat spared.
As the prosecution proceeds, amid continuing developments and revelations, discussion of the case has often narrowed to a few key areas.
Some of these questions — What’s next? How did this happen? — have answers, if only partially. Others are mysteries that may never be fully solved.
1. How Did the Family Allegedly Keep Such Extreme Abuse Hidden?
Speaking to reporters on Jan. 18, Riverside County, California, District Attorney Michael Hestrin said, “It appears no one noticed what was happening.” He detailed a few pieces of information from the investigation that show how this could have been the case.
For example, Hestrin said, the Turpin family was regularly sleeping all day and up all night.
What’s more, the six minor children were officially being home-schooled so they rarely had to leave the house and were kept off the radar of outsiders such as teachers, coaches or counselors.
The family also had a history of relocating. Though David and Louise reportedly grew up in Princeton, West Virginia, they later moved to Texas where they lived for 17 years after marrying in February 1985, when she was 16 and he was 23.
In 2010, they moved from the greater Fort Worth area to Murrieta, California, and then from Murrieta to nearby Perris in 2014.
As they relocated, the abuse of the children only intensified, Hestrin alleged at the Jan. 18 news conference.
Separately, he told PEOPLE, “Crimes that occur within a family like this are by their very nature difficult to uncover because they happen at night, under the cover of darkness, behind closed doors. They happen in secret, so there has got to be something that uncovers what happened in the dark and in the secret of this family.”
Neighbors have reported having limited contact with the Turpins, and Louise’s brother, Billy Lambert, told PEOPLE he was unable to speak with his nieces and nephews, despite repeated requests.
“They were a little odd, but I didn’t see anything to call authorities for,” neighbor Wendy Martinez told PEOPLE.
When another neighbor and her son saw three Turpin kids putting up Christmas decorations in 2015, she said they were taken aback by the interaction.
“We said, ‘Oh, the decorations look so nice,’ and they froze,” Kimberly Milligan recalled. “Like when young children want to divert a threat they think they can pretend to be invisible. … That was the last time the family put out Christmas lights.”
2. What May Have Motivated the Parents?
Much about the family’s behavior is still unclear, including why the suspected abuse allegedly escalated over time and how the parents were able to control their children so absolutely, especially when the oldest ones are in their 20s and at least one son was enrolled in college.
Hestrin was asked about a possible motive on Jan. 18 and said, “I don’t know that I can answer that completely. As a prosecutor, there are cases that stick with you, that haunt you … sometimes in this business we’re faced with looking at human depravity and that’s what we are looking at here.”
The son in community college was always chaperoned by his mother, Hestrin said.
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As to the possibility of a cult or religious element in the family’s behavior, Hestrin said, “Not that I know, no.”
When asked if the children were brainwashed, he said he’d be “speculating.”
Lambert, Louise’s brother, said she and David had met in church and “ran away” to Texas to marry in 1985 before being returned to West Virginia, where Louise’s father consented to the nuptials.
Louise had her first child at 20, Lambert said.
“She had mentioned the Kate Plus 8 show, that it was a cool reality show,” he said. “I think deep down that is what she wanted [a big family].”
3. The Teen Girl Who Escaped — Where Did She Get a Phone?
The conditions inside the Turpin home were only made public after one of their children, a 17-year-old girl, escaped the home before sunrise on Jan. 14 and then called 911. Authorities believe she likely slipped out of her bedroom window.
But how did one of the siblings, whose activities appear to have all been tightly controlled, get access to the phone that put her parents behind bars?
Authorities have not confirmed how the teen came to acquire the device, which was deactivated at the time she used it, meaning it allowed her only to place an emergency call.
“The girl, with several of her siblings, had been discussing some kind of escape plan,” Hestrin told PEOPLE. “For up to two years they at least thought about escape. As to why they chose that day or that time, I just don’t know. I think we will know more when we get this case ready for preliminary hearing.”
4. Dad Is Accused of a Sex Crime. Are There More Charges to Come?
In addition to the dozen charges each of torture and false imprisonment that David and Louise face, they are also accused of seven counts of abuse of a dependent adult and six count of child abuse.
But David faces an accusation that Louise does not: He is charged with one count of lewd act on a child under 14, though authorities have not elaborated further on their allegation he was sexually abusive.
“About the only thing the children were allowed to do while chained up or in their rooms was to write in journals,” he told reporters. “We now have recovered those journals — hundreds of them — and we are combing through them for evidence.”
“If our investigation uncovers more crime, we will file more charges,” Hestrin said in January. In late February, more charges were indeed filed against both parents: three new child abuse charges each for David and Louise and one felony assault charge against Louise, according to an amended criminal complaint.
Attorneys for David and Louise, who are barred from contacting their children, have declined to comment on the case beyond broad reactions to the seriousness of the allegations.
5. One of the Kids Previously Tried to Escape in Texas, So Why Wasn’t the Family Discovered Then?
A former neighbor of the Turpins told PEOPLE in late January that one of the siblings tried to get free years ago when the family lived in Rio Vista, Texas.
“One of the girls escaped and I was always told that the police returned her,” said Rick Vinyard. “One of the girls did try to run away. It was probably three or four years after they moved in.”
Vinyard said that the Turpin family first lived in a brick house across the street from him. In time, he said, the family moved out of that home and into a double-wide trailer parked on the same lot.
“They moved out of the brick house because the family had trashed it so bad, it was unlivable,” Vinyard claimed. “They had left pets in there that starved to death. We found a dead dog and a dead cat in that house. The kitchen just looked horrible. There were dirty diapers piled waist-high.”
The Turpins moved to California after 10 years in the neighborhood, Vinyard said. They left behind a “filthy” house that contained “barracks”-like bedrooms and a “makeshift school,” other Texas neighbors said in April.
But it seems that, just as in Riverside County, no red flags were raised until the teenage girl’s escape.
“We researched thoroughly and we didn’t have any reports,” a spokesman for Texas’ Department of Family and Protective Services told PEOPLE in January.
An official with the Hill County sheriff in Texas said that while authorities had some long-ago interactions with the Turpins, they were relatively minor.
In 2001, the family dog bit their 4-year-old daughter and the girl was hospitalized and the dog put down, Chief Deputy Rick White told PEOPLE. And in 2003, “Their pigs got out and ate the neighbor’s dog food. They replaced the dog food and the trash can that the pigs tore up.”
Speaking about the revealed allegations against David and Louise, Hestrin, the prosecutor, praised the teenager who exposed them.
“I think we are very happy and fortunate that the girl mustered the courage to do what she did when she did it,” he said in January. “It is an unbelievable story. It really is.”
Anyone with information about the Turpin family is urged to call 888-934-KIDS.
• With reporting by ELAINE ARADILLAS, K.C. BAKER, JASON DUAINE HAHN, CHRIS HARRIS and CHRISTINE PELISEK