In Austria, Elisabeth Fritzl has begun being questioned by legal authorities.
She has recently been freed from the cellar in which her father, Josef, kept her captive for 24 years.
The prosecutor’s office said that a doctor was involved in the questioning, in order to determine how one of the seven babies that she was forced to bear by her father had died.
Mr Fritzl confessed to incinerating the body of the dead baby, said officials.
Within a few months, formal charges against Josef Fritzl may be ready, which will allow a trial to start later this year.
Officials said that the interview was being filmed so that Elisabeth Fritzl will not have to give evidence in person in court.
How long the questioning will last or where it is taking place remains unclear.
While Mr Fritzl is being held in pre-trial detention in St Poelten, 80 km west of Vienna, the capital, Elisabeth, 42, and his other alleged victims are undergoing treatment at a psychiatric hospital.
Mr Fritzl has confessed to keeping his daughter captive in a cell at his home in Amstetten, where he says he had seven children with her, prosecutors say.
Three of the children were raised above ground while three were confined to the cellar with their mother, and one died in infancy, officials say.
If he is found responsible for the death, Mr Fritzl, who confessed to disposing of the child’s corpse, a twin born in 1997, could face murder charges, officials add.
DNA tests have shown he is the father of Elisabeth’s six surviving children.
The case came to light when Kerstin, one of the children fathered by Mr Fritzl, became seriously ill and was taken to hospital. As they were unable to find any medical records, they appealed for the teenager’s mother to come forward. Mr Fritzl released Elisabeth, who then explained the story to police.
Earlier this month, after coming out of a coma, Kerstin was finally reunited with her family and is expected to make full recovery.