The daughter of accused abductor Dorothy Barnett will travel from Australia to the US to ask a judge to free her mum from jail.
The US woman accused of abducting her infant daughter and travelling the world as a fugitive for almost 20 years before her arrest on Queensland's Sunshine Coast fears she may have breast cancer.
Dorothy Lee Barnett, 54, is locked up in a South Carolina jail after her extradition from Australia last month and has made a passionate plea for bail.
Her lawyer has told a US District Court judge in Charleston that Barnett has been held in jails in Australia and the US since her arrest in Queensland last November and her health has "deteriorated significantly".
The daughter Barnett is accused of abducting, 21-year-old Savanna Todd, who lives in Australia under the name Samantha Geldenhuys, still supports her mother and will travel from Queensland to South Carolina for a yet-to-be scheduled bail hearing to ask for her mother's release.
Barnett has lost seven kilograms during her incarceration, suffers from high blood pressure and has a large lump on her left breast that was discovered while in a jail in Australia, her lawyer Russell W. Mace said.
"Ms Barnett believes this lump has possibly changed shape and size and is seeking medical attention at Charleston County Detention Center," Mace told Judge Richard Gergel in a court filing.
"However, Ms Barnett wishes to consult a specialist for her medical issue and would be better able to do so if released."
It was only after US authorities received a tip and Barnett was arrested in Queensland that her daughter discovered she was not who she thought she was.
Savanna's father, Benjamin Harris Todd III, had been embroiled in an ugly child custody battle in South Carolina in 1994 with Barnett when Barnett disappeared with the baby during a supervised visit.
It is alleged Barnett took Savanna to South Africa and New Zealand before settling in Queensland.
Todd never gave up the search for his daughter.
Barnett faces 30 years in jail if found guilty of international parental kidnapping and falsifying US passport application charges.