London, May 27 : After fighting for her life for weeks, cellar kid Kerstin has miraculously woken from her coma.
Medics feared that the 19-year-old - born to Fritzl and his daughter Elisabeth during her 24-year incestuous captivity - would die when her organs failed earlier this month.
But she showed flickers of life over the weekend and on May 26 the family were overjoyed to hear she had opened her eyes.
"In a world that was very dark, the Fritzls now have light," the Mirror quoted a source, as saying.
"Elisabeth and family are very happy, but they know they mustn't get their hopes up too high. Kerstin's incredibly fragile. She'll be in bed a long time - probably months," the source added.
The source said: "Kerstin has not yet spoken but she's responding to touch. She moves when she feels pressure on her skin. Everybody's crossing their fingers this recovery will continue but nobody can predict it. Doctors are still piecing together Kerstin's medical history.
"Elisabeth has helped hugely with that and has had several sessions with doctors to fill in the gaps. But there are some things people simply don't know. Elisabeth is doing a wonderful job of getting the family back to normal. Kerstin is the final piece of the jigsaw."
Kerstin became desperately sick after getting no fresh air, light, exercise and proper food her entire life in the cellar.
In a rare act of mercy, Fritzl, 73, chose to release the teenager and take her to hospital when she collapsed in his underground lair last month.
If she gains strength, police will quiz her on whether Fritzl sexually abused her.