A couple facing trial over the torture and false imprisonment of their 13 children had four more charges filed against them on Friday in a California court.
The Riverside County district attorney filed three further charges of child abuse against David and Louise Turpin, and one count of felony assault by Mrs Turpin against one of her children.
The couple are pleading not guilty to all 42 charges, including torture, false imprisonment, abuse of a dependent adult and child abuse, as well as one count of lewd conduct with a minor against Mr Turpin.
Lawyers for the couple said they are both pleading not guilty to the additional charges filed on Friday.
"Today we filed an amended complaint in the Turpin case this afternoon," said John Hall, spokesman for the district attorney's office, speaking outside court after the hearing.
"We have amended the complaint to file three new charges on both defendants of child abuse, and one new count against only defendant Louise Turpin of felony assault.
"There have been no counts that have been removed, and no other additional counts other than those.
"It's further investigation that we've been doing in this case has led us to amend the complaint. That's not uncommon in cases," he added.
"It could add some time to the exposure that they're facing, I don't have that tabulated right now."
Mr Hall said he was not aware of any changes to the charges filed against the couple last month.
Evidence which will be passed to the defence in discovery includes "voluminous" video and audio recordings, and physical evidence, according to Dave Macher, attorney for Louise Turpin.
A new Felony Settlement Conference was set for March 23, where the attorneys for all sides will discuss the charges with the judge, and a new preliminary hearing was scheduled for May 14.
The May hearing will likely involve testimony from police officers involved in the case, without the Turpin children being present, Mr Hall said.
David Turpin appeared in court dressed in a black suit with a blue shirt, and had trimmed his hair since his first court appearance.
He sat facing forward, with a lawyer sat between him and his wife.
Mrs Turpin wore a fitted black suit and turned to watch the scores of journalists, law enforcement and public file into the court.
The two defendants spoke only to confirm the date of the next court hearing.
The Turpins' children, aged between two and 29, have been taken into care and are split between two foster homes, sources say.
Having lived under the tyrannical and abusive rule of their parents their whole lives, the children have not experienced many of the things other children take for granted - they are currently being introduced to iPads, Harry Potter movies, and even toothbrushes.
The alleged abuse was revealed when one of the children, a 17-year-old girl, escaped out of a window at their house in Perris, California, and called 911.
Police arrested David and Louise Turpin at the property last month.
Mike Hestrin, Riverside County district attorney, said police found the girl's 12 siblings inside the four-bedroom home, padlocked and shackled to the furniture, lying in their own urine and faeces.
All 13 children were hospitalised, and were so malnourished they were at risk of shock. The eldest child, a 29-year-old woman, weighed just 82lbs (5 stone) when she was rescued.
Officials said a total $570,000 has been donated from around the world to help pay for their healthcare and education.
"In cases like this there are long-term needs like behavioral health, housing, scholarships, educational support, tutors and medical needs," Erin Phillips, a spokeswoman for the Riverside University Health System told CNN.
"It's been amazing the outpouring of love and sentiments," Phillips said. "It reminds us there is so much light in this world in contrast to such a dark case."
Jack Osborn and Caleb Mason, lawyers who represent seven of the older children, said that staff had converted a ward at Corona Medical Center to make them more comfortable, with an outdoor area where they can exercise and play sports.
"That in itself is a new experience for them, understanding that they do have rights and they do have a voice," Mr Osborn told CBS.
"That's a big deal, deciding what they're going to read, deciding what they're going to wear, these are all things that are decisions they make every day that are new and empowering."
Corona mayor Karen Spiegel said nurses at the hospital looking after the Turpins' children told her they were "warm" and "appreciative".
"They talk about how warm and loving these kids are and so appreciative," she said. "Some of them have never really seen a toothbrush before... Things that we just take for granted mean so much to these kids."
Detailing the allegations against the Turpins at a press conference last month, Mr Hestrin said the children were "hogtied" and subject to "frequent beatings and even strangulation".
"As a punishment starting many years ago they began to be tied up, first with ropes," he said. "One victim was tied up and hogtied. When that victim was able to escape the ropes the defendants started using chains and padlocks.
"These punishments would last for weeks or even months," he added. "The victims were often not released from their chains to go to the bathroom."
Mr Hestrin said the couple engaged in the psychological torture of their children, taunting them at their home with toys and food that they were not allowed to touch.
Police are understood to be still combing through a stack of the children's journals recovered from the house, looking for further evidence of the alleged abusive treatment by their parents.