After bringing the Obama administration into the negotiations for Kayla's release, the Muellers got threats from the Department of Justice of prosecution if they or others paid a ransom, a point which ABC brings up again in this story.
Former Islamic State (Isis) hostages have offered accounts of what they witnessed of the treatment of U.S. aid worker Kayla Mueller who was abducted by the terror group in 2013.
Four former prisoners, who were held with Mueller, tell ABC News that Mueller stood up for her Christian faith while in captivity, even to the fearsome, notorious executioner "Jihadi John".
'But somewhere in a boardroom, they chose to leave our daughter there to be tortured and raped and ultimately murdered'.
The Muellers reveal to Ross the emails they exchanged directly with ISIS, attempting to negotiate for their daughter's life and the proof-of-life video sent to them of Kayla begging for help.
"They would scream at her, and they would, you know, blame her for everything that America has done in the world", Saide said. "I don't think so", Rye said.
"I've been here too long, and I've been very sick".
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"I saw how thin she looked, but I saw that her eyes were very clear and steady", said her mother, Marsha. Kayla's heartbroken father was interviewed in an episode of "20/20" set to air on Friday.
Mueller was taken hostage with her boyfriend, Omar Alkhani in August 2013 after leaving a Doctors Without Borders hospital in Aleppo, where he had been hired to fix the internet service for the hospital.
On Aug. 23, her parents released a copy of an unpublished letter she wrote while in captivity, per the Daily Mail, which further explained her selfless dedication to others.
"You just go into nearly a catatonic state, I think".
She told me, 'No, because I am American. "She converted to Islam.' And then she was like, 'No, I didn't, '" Ottosen said in an interview for the 20/20 The Girl Left Behind programme. And this evening, you will hear from her parents, who say the President made them a promise - a promise, they say, that was not kept. And why they leave her out there like that?
Little was known about the Islamic State group at the time, still months before President Barack Obama referred to the growing Sunni extremist group as the "J.V. team", compared to al-Qaida.
Kayla Mueller was subjected to torture, slave labor and was raped by Daesh leader Abu Bakr al-Baghdadi before she died February 2015.
