Kayla Mueller's Family: Bowe Bergdahl Deal Hurt Her Chances for Freedom

Matt Hinshaw/The Daily Courier/AP Kayla Mueller

The family of 26-year-old Kayla Mueller has spoken out in the wake of her death while in ISIS captivity.

"We always had that little bit of hope that we would always get her home," her mother Marsha told the Today show in an interview that aired on Monday.

Initially, her family hoped to negotiate the release of the Arizona native with a $6.2 million ransom payment.

"I really feel that we had a chance to get Kayla out," her father Carl said. "We were in communications with them, unlike other families. But how do you raise $6.2 million? You know, it pretty much made it impossible."

Any hope truly died when the United States traded five Taliban detainees for Army Sgt. Bowe Bergdahl in May 2014, the Mueller family says.

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"That made the whole situation worse," Mueller's brother, Eric, explained. "Because that's when the demands got greater. They got larger. They realized that they had something."

He added: "They realized that, 'Well, if they're gonna let five people go for one person, why won't they do this? Or why won't they do that?' "

Mueller, an American aid worker, was taken hostage in Syria in August 2013. She was confirmed dead on Feb. 10, four days after ISIS claimed that Mueller had been killed by a coalition airstrike near Raqqa, Syria.

Her father acknowledges that his daughter's decision to travel abroad to such a dangerous country was "na?ve."

"How many mistakes have we all made in life that were na?ve and didn't get caught at?" he asked. "Kayla was just in a place that was more dangerous than most. And she couldn't help herself. She had to go in there and had to help."

Though he understands the U.S. government's decision not to risk the lives of soldiers to rescue his daughter "without knowing exactly the circumstances," he thinks the government could have acted more quickly.

"Yeah, I think they waited too long," Carl said. "Through people that have gotten released, we had an idea of where they were, a real good idea where they were."

On Monday, the family announced that they had started a foundation in their daughter's name. Kayla's Hands will support causes Mueller felt passionate about.

"She had to be busy with her hands doing something to help people. And as long as she was, she was just joyful," her mother said.