Charges including torture and child abuse have been brought against the parents of 13 children in California.
The siblings - who range in age from two to 29 - did not know what medication or a police officer was, and were often beaten and tied up as punishments.
One of the children managed to escape from the house in Perris on Sunday and call the police.
David Allen Turpin (57) and Louise Anna Turpin (49) will appear in court later on Thursday to face the charges.
Prosecutors say one of malnourished children allegedly held hostage by their parents had planned her escape for two years.
Authorities say the children were held all in one room, and allowed only one shower a year.
There have been 12 charges of torture filed against both parents.
One charge of a lewd act on a child by force or fear has been filed against the father.
The lewd act was against a female under 14.
There are seven charges of abuse of a dependent adult and six charges of child abuse.
There are also 12 charges of false imprisonment.
David Allen Turpin and Louise Turpin are pictured with their children | Image: Facebook
Michael Hestrin is the Riverside County District Attorney.
He said: "The children were, when they were not changed up, locked in different rooms and fed very little on a schedule.
"The children lacked... a basic knowledge of life - many of the children didn't even know what a police officer was.
"A 17-year-old, when asked if there was medication or pills in the home, didn't know what medication or pills were".
The children were found at their parents' home in Perris, which is about 70 miles east of Los Angeles.
After the 17-year-old girl alerted police, a welfare check was carried out and the grim discovery was made.
Police said the children were found "shackled to their beds with chains and padlocks in dark and foul-smelling surroundings".
Speaking at a news conference on Tuesday, Riverside County Sheriff's Office police chief Gregory Fellows said it was not clear how long the family had been held in such conditions but that it appeared to have been for a "prolonged period".
Three of the siblings were found chained to furniture, he said. Six of the children are minors, while the other seven are over 18.
Their parents are being held in a detention centre on US$9m (€7.3m) bail ahead of their court appearence.