Anonymous tips have led German police and youth welfare officers to discover an eight-year-old girl who has spent most of her life locked in a room by her mother.
The child was found in Attendorn in the German Sauerland region in September, police revealed this week.
She is said to be doing well given the circumstances. There were no indications of physical abuse.
German broadcaster WDR reported the girl was now in foster care.
The local public prosecutor has made an application to appoint a supplementary court guardian, stating that the girl's biological parents, or at least the mother, can no longer decide for the child.
It is not yet clear why the mother kept her child hidden for years. Investigators said they assume the girl has not been allowed to leave the house since she was one and a half years old.
According to the investigation, the mother told authorities and the father's child, who she was separated from, that she was moving to Italy. Instead, she remained in Attendorn, allegedly living with her parents.
The mother and grandparents have not said anything about the accusations.
Youth welfare officers and police became alerted due to anonymous tips, but multiple attempts to enter the house were unsuccessful due to the residents refusing entry.
After confirmation from Italian authorities that the mother and child had never lived in Italy, German police obtained a search warrant and found the girl.
According to the local prosecutor, the girl was examined in a children's clinic. She said the girl had never seen a forest before, been in a meadow or driven in a car. Instead, she spent the majority of her life in a room with the door locked.
Despite never having been to a kindergarten or school, the girl was able to read and count.
Although the child was not malnourished, she did not come out unscathed. She was hardly able to walk up stairs and struggled when walking.
The prosecutor has charged the mother with deprivation of liberty and mistreatment. The grandparents are also under investigation.
