Ms Nettleton’s grandchildren were smuggled into an IS-controlled region of Syria by their father, convicted Australian terrorist Khaled Sharrouf.
She had travelled to Turkey in an attempt to rescue them, but on the day she arrived a Sydney newspaper ran a front page article revealing her intent.
That article was the beginning of a media whirlwind which ended her long-held plan.
Intense media attention scared off people who may have helped Ms Nettleton, and earlier this week she was advised that staying in Turkey would only increase the risk to her and her grandchildren.
So she decided to go home without her family.
“It’s horrible. I envisioned them taking up a whole row of seats, and Hamze running up and down the aisle. The baby crying. And now it will just be me,” Karen told 7.30 as she prepared to leave the Turkish capital Ankara.
The children are: Zaynab, 14; Hoda, 13; Abdullah, 11; Zarqawi, 10; Hamze, 5; and Zaynab’s four-month-old baby Aiyesha.
On Thursday Ms Nettleton arrived back in Sydney, distraught by the failure, but still determined to one day see her grandchildren brought home to safety.
“I’m coming back, I’m not going to leave them here … it might take three, four, five attempts. Don’t underestimate the determination of this nanna,” she said before she departed.
Ms Nettleton was questioned by officers from the Australian Border Force’s Counter Terrorism Unit after arriving in Sydney on a flight from Abu Dhabi.
She was released after an hour of questioning.
In February 2014, Ms Nettleton’s grandchildren were taken to Turkey by their mother and her daughter, Tara Nettleton.
They were then smuggled into Syria by Khaled Sharrouf.
They remained there with their mother until September last year, when she died of an untreated illness.
Sharrouf was reportedly killed in a June 2015 air strike, but Australian authorities have long held doubts.
Recently, they intercepted phone calls to Australia from Syria by someone claiming to be Sharrouf.
Australia Government, media hindered rescue attempt: lawyer
Ms Nettleton’s lawyer, Robert Van Aalst, accompanied her to Turkey.
He said they were hindered from the start by media reporting and what he says was the unhelpful behaviour of the Australian Government.
“We’ve decided to leave because we found that our presence here in Turkey attracted media attention,” Mr Van Aalst said.
“We’ve also decided to leave because the Australian Government has continued not to be of any assistance whatsoever, and in fact in my view have put up roadblocks.”
The Government previously said it was unable to enter Syria to provide assistance to the children.
“We have very limited consular capacity in Syria,” Foreign Minster Julie Bishop said when Ms Nettleton’s trip was first revealed.
“We do not have an embassy in Damascus and it is against the law for an Australian citizen, without lawful reason, to be in Ar-Raqqa and parts of Iraq.”
This post originally appeared on ABC News.
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