The jihadi widow of Australian Islamic State terrorist Khaled Sharrouf has reportedly died in Syria.

Tara Nettleton, a Muslim convert originally from Sydney, is believed to have passed away last year following complications associated with appendicitis.

Family friend Robert van Alst told The Sydney Morning Herald that the 31-year-old's mother, Karen Nettleton, had only recently been informed.

"She said it was the worst day of her life. And it was made worse because she could not be with her daughter when she was dying to give her comfort," he said.


Mr van Alst said Karen is extremely worried about her daughter's children, who are just "innocent Australian kids".

Tara was reportedly living in Raqqa with four of her five children and one grandchild after the death of her husband.

She had fled to Syria in February 2014, just months after her husband slipped out of Australia to join friend, Mohamed Elomar, in the ISIS stronghold.

Tara told relatives she was taking her family on a "cultural" visit to Turkey following a trip to Malaysia, but instead travelled to Syria.

During her time in Syria, Tara shared pictures with a number of other jihadi brides, holding rifles and ISIS flags.

Her husband Sharrouf sickened the world by sharing a picture of his son holding the severed head of a Syrian soldier with the caption, "That's my boy."

Sharrouf, Australia's most notorious terrorist, was reportedly killed in drone strikes last year, along with Elomar.

However some of his friends last year claimed his death was faked in an elaborate plot.

Australian authorities had always been sceptical about reports of the terrorist's demise and government sources had cautioned that it was in Sharrouf's interest to appear dead.

Charles Waterstreet, the lawyer for the Nettleton family, said Tara and her children claimed Sharrouf was dead.

"The family have held ceremonies for him and it would be an elaborate ploy if he wasn't," he said.

The Nettleton family had previously lobbied authorities to extract Tara and her children Zaynab, 13, Hoda, 11, Abdullah, 10, Zaqawi, 9, and Humzeh, 4, from Syria.