Transcript for Never-Before-Seen Video of ISIS Hostage Kayla Mueller
We appreciate it. To the heart-breaking and inspiring case of Kayla Mueller. Our chief investigative correspondent Brian Ross is here with the untold story. Good morning, Brian. Reporter: Good morning, George. She was the girl left behind. Just three years ago this month that that young American woman from Arizona, Kayla Mueller, was taken hostage by Isis. This morning, we're hearing from her parents about their determined fight for her freedom. ? the home movies show a young woman full of life. Traveling the world to help the innocent victims of war. My name is Kayla Mueller. Reporter: That all ended with this vizio, being seen this morning for the first time. I've been here too long. I've been very sick. It's terrifying here. Reporter: Kayla Mueller was taken hostage by Isis on what was supposed to have been a quick trip into Syria. As Isis brutally murdered three young American men. I'm back, Obama. Reporter: The plight of a fourth American hostage, Kayla, remained a closely held secret. Her parents, mar shall and Karl, worked desperately to gain her freedom. Sending their own videos to Isis. Please, show mercy and use your power to free you are a daughter. Reporter: There would be some 27 e-mails back and forth between the couple in their kitchen in Arizona and Kayla's captors in Syria. Who, at one point, set a deadline. Or we will send you pictures of her dead body. A white house official threatened them with prosecution if they paid ransom for their daughter. Somehow we survived. I remember the argument, mar shall, we need to do something. They're not going to bring Kayla home. Reporter: A year and half after she was captured. Isis sent the muellers three pictures of their daughter's dead body. The they said the president made a promise to help the foundation set up in Kayla's name. And broke it. He says, I will help that donation. You won't know. It will be an anonymous donation. But I will. I'm still waiting. Reporter: There hasn't been such a donation? No. I'm still waiting for that donation. Mr. President. You see the flag at my driveway. It's not something I take lightly. Talking about our president that way. But that's what he said. Reporter: The white house is now confirmed to ABC news that the president has indeed not yet made the donation he promised some 17 months ago. But an official said he still intends to, George. You can see the is appointment in their eyes. In the story tonight, you have interviews with her fellow hostages who tell the story of a remarkably selfless woman. She put herself last after them. She had a chance to escape and decided not to because it would endanger other hostages. Thank you, Brian. Tune in to "20/20" tonight. Up next on the big board.
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