The condition of convicted child killer Valmae Faye Beck, formerly known as Fay Cramb, has improved and it is believed she is out of a coma.The Department of Corrective services said Beck was now in a stable condition in the Townsville General Hospital.Beck was in a medically induced coma following complications with heart surgery.It is believed she is still not speaking.Beck and her former husband Barrie Watts were jailed for life in 1987 for the torture and murder of Noosa schoolgirl Sian Kingi.Cold case detectives want to interview the 64-year-old high security prisoner over more unsolved crimes, hoping for confessions as she faces her own mortality.Detectives believe the notorious criminal may know the fate of several unsolved cases involving young girls and women across Australia.In August 1995 a Supreme Court jury in Brisbane acquitted Watts of murder and a lesser charge of manslaughter in relation to the death of a woman whose body has never been found.Watts pleaded not guilty to murdering Helen Mary Feeney, a 31-year-old student, between October 29 and December 1, 1987.Beck testified that Watts had dumped Ms Feeney's body and burned it at a rubbish tip near Lowood, west of Brisbane.But detectives believe the body was actually disposed of elsewhere and Beck knows the location.Beck has been questioned about the disappearance of 14-year-old Sophie Helen Woodman, who went missing on March 21, 1980, after leaving her Perth home with a girlfriend and travelling to the eastern states.She and Watts have been linked to the murders of Sharron Phillips, 20, in Brisbane's outer west, Stella Mary Farrugia, 19, and Louise Bell, 10, in Adelaide.Treatment of morbidly obese Beck sparked a public outcry with Premier Anna Bligh forced to defend her rights to taxpayer-funded health care."While I understand that people might have some questions about this, in this country we don't have a death penalty - we do provide medical services to people who are in our prisons," Ms Bligh told reporters in Brisbane.Two prison officers have been posted at Beck's hospital bedside with concern she may be a target for reprisals rather than posing any threat given her medical condition. AAP