Who is Kayla Jean Mueller? Read the ISIS captive’s letter to family

WATCH ABOVE: The family of Kayla Mueller say they now know the fate of their daughter. CBS News reporter Craig Boswell has more details from Washington.

Kayla Jean Mueller’s parents on Tuesday confirmed the news they had long feared: after 18 months of being held by ISIS, their daughter was killed.

ISIS supporters claimed last week the American aid worker had died in a Jordanian airstrike, but that allegation was met with skepticism.

“There’s no evidence of civilians in the area prior to the coalition strike,” Earnest told reporters, White House Press Secretary Josh Earnest said in a media briefing on Tuesday.

Her precise cause of death is not known, nor is the timing of when she died, Earnest said.

READ MORE: Jordan calls ISIS claim that American hostage killed in airstrike a ‘PR stunt’

But what is known about the 26-year-old is that she was a tireless humanitarian. “Kayla was a compassionate and devoted humanitarian. She dedicated the whole of her young life to helping those in need of freedom, justice, and peace,” her parents Carl and Marsha Mueller said in a statement on Tuesday.

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“Kayla was drawn to help those displaced by the Syrian civil war. She first traveled to Turkey in December, 2012 to provide humanitarian aid to Syrian refugees. She told us of the great joy she took in helping Syrian children and their families.”

Kayla Jean Mueller was kidnapped by ISIS in Aleppo, Syria on Aug. 4, 2013, the 26-year-old’s family confirmed through a spokesperson. Mueller family handout

READ MORE: UAE launches airstrikes from Jordan on ISIS targets

Mueller, from Prescott, Arizona, has been involved in several humanitarian efforts since graduating from Northern Arizona University in 2009, including work with Syrian refugees on the Turkey-Syrian border through the Danish Refugee Council and with Turkey-based Support for Life.

She also carried out humanitarian work in northern India and Israel and Palestine, as well as spending a year working at a local HIV/AIDS clinic and a women’s shelter in Arizona.

Mueller once explained her reasons for such humanitarian work by saying: “I find God in the suffering eyes reflected in mine, if this is how you are revealed to me, this is how I will forever seek you.”

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A May 2013 article in Prescott’s The Daily Courier reported Mueller once helped reunite a Syrian man with his then 6-year-old child, after the bombing of a Turkish refugee camp.

WATCH: President Obama speaks out about the death of Kayla Mueller.

“This is the reality for Syrians two and a half years on. When Syrians hear I’m an American, they ask, ‘Where is the world?’ All I can do is cry with them, because I don’t know,” The Daily Courier reported Mueller saying. “Syrians are dying by the thousands, and they’re fighting just to talk about the rights we have.”

She said she found “joy” in the work that she did and she would “not let this suffering be normal.”

READ MORE: What if a Canadian pilot is shot down in ISIS territory?

A 2007 profile in the same publication detailed her volunteer work with the Save Dafur Coalition, promoting awareness of victims of the Sudanese conflict — which many human rights groups have labeled a genocide.

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“I always feel that no matter how much I give I always get back more through these projects,” she told The Daily Courier when she was just 19 years old.

In this May 30, 2013, photo, Kayla Mueller is shown after speaking to a group in Prescott, Ariz.
In this May 30, 2013, photo, Kayla Mueller is shown after speaking to a group in Prescott, Ariz. AP Photo/The Daily Courier, Matt Hinshaw

“We are so proud of the person Kayla was and the work that she did while she was here with us. She lived with purpose, and we will work every day to honor her legacy,” the Muellers wrote in their statement.

Mueller had just left a Spanish Medecins Sans Frontiers/Doctors Without Borders hospital in Aleppo when ISIS militants captured her on Aug. 4, 2013, although she was not working with that organization.

Along with confirming the news of her death, the Mueller family released a letter they received from their daughter in spring 2014, via a former ISIS captive who had been released.

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“If you could say I have ‘suffered’ at all throughout this whole experience it is only in knowing how much suffering I have put you all through,” she wrote in her last letter. “I have been shown in darkness, light + have learned that even in prison, one can be free. I am grateful. I have come to see that there is good in every situation, sometimes we just have to look for it.”

Read the letters from Kayla Jean Mueller below

Mueller’s parents said they “remain heartbroken… for the families of other captives who did not make it home safely.”

Mueller was the last known ISIS hostage from the U.S. ISIS murdered captive freelance journalists James Foley and Steven Sotloff last summer, and American aid worker Abdul-Rahman (Peter) Kassig in November. ISIS executed British aid workers David Cawthorne Haines in September and Alan Henning in October. ISIS beheaded all five men and posted videos, showing their bodies, online. British journalist John Cantlie, who has been held hostage since November 2012, is still being held captive.

READ MORE: After Kassig, ISIS still holding John Cantlie and female U.S. aid worker

The Mueller family requested, for those wishing to honour their daughter and her work, that donations be made to causes she “would have supported.”

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Spring 2014 letter from Kayla Jean Mueller

Transcribed letter from Kayla Jean Mueller

Please note: Portions of this article have been taken from an earlier article about Kayla Jean Mueller, published by this author

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