For the first 13 years of her life, "Genie" was confined to her bedroom, strapped to a toilet by day and bound in a sleeping bag under a metal screen in her crib at night.
Her only human contact was with her father, who beat her every time she vocalized, and barked at her like a dog to quiet her. By the time Genie was liberated in 1970, the child was nearly mute, uttering only a handful of phrases, including "stopit" and "nomore."
The girl was known for her "bunny walk," because she held her hands like paws, and her social interaction was limited to sniffing, spitting and clawing.
This American horror story, explored in the 2001 film "Mockingbird Don't Sing," bears a striking resemblance to another horrific case of abuse that played out in Austria this week.
Police learned that three children had been locked with their mother in the basement of their grandparents' home their entire lives, imprisoned by their 72-year-old grandfather. Although they spoke some German to authorities, the prisoners reportedly spoke to one another only in growls.
"It's as though they were kidnapped by aliens and woke up on another planet," Dr. Stuart Goldman, director of psychiatric education at Children's Hospital in Boston, told ABCNEWS.com. "The impact will be dependent on the age of children, and the younger are more likely to recover."
In addition to experiencing health problems, these children will struggle in their attachments to other people, language development and in their capacity for self-regulation, and in many other areas, Goldman said.
"A scientist can't predict because there are few valid comparisons," he said. "Sporadic reports are that feral kids have not adapted well."
While German doctors attempt to unravel the toll the abuse has taken on these children, Genie's case offers some clues. The so-called "feral girl" had the best psychiatric help and most devoted foster care, but she never overcame her wounds.
"Their forever is compromised," said Alice Honig, professor of child development at Syracuse University. "Genie was given every bit of love and lessons and experts in language development, but she never recovered."
The Austrian children were exposed to television but had no books or outside stimulation. "Learning cannot take place without human love and care and interactions," said Honig.
German psychologist Bernd Prosser agreed in an interview on Austrian television: "The four will never be able to live normal lives. I am afraid it is too late for that," he said.
Josef Fritzl, 72, imprisoned his now 42-year-old daughter Elisabeth for 24 years, repeatedly raping her and fathering her seven children. One died, three were raised upstairs with Fritzl and his wife, Rosemarie, and three others were confined to a three-room, cramped cellar with their mother.
Rosemarie Fritzl had reportedly been told her daughter had joined a cult and told police she knew nothing about the children downstairs.
Police found the sadistic lair after 19-year-old Kerstin, one of the children living in the basement, fell into a coma and Elisabeth persuaded her father to take the girl to the hospital. Hospital officials grew suspicious and called police, who made the discovery at the family home.
When the children emerged into daylight, 18-year-old Stefan made a squeaking noise and covered his face with his hands. Later, he made gurgling noises when he saw a cow.