An anguished mother has described in court how she begged her Muslim convert son not to go to Syria - months before he was killed in battle.
Sue Boyce told jurors how her son Jake Petty only informed his family of his plans after he had left his home in the summer of 2014.
By the end of the year, he had been killed in battle and Ms Boyce later identified his body from video footage, jurors at the Old Bailey heard.
Petty, 25, was allegedly one of a group of friends from Walsall, West Midlands, who left Britain in 2014 to join Islamic State.
His mother was giving evidence in the trial of Lorna Moore, 33, who is accused of failing to inform police her husband Sajid Aslam was poised to leave for Syria.
Ms Boyce told jurors: "I had no idea Jake had thoughts of going to Syria. There were Sunni Muslims involved in Islamic State but he was quite horrified by what he saw watching it on TV."
Petty, who had a twin brother and two sisters, had left the country in July bound for Athens and then on to Cairo before crossing into Syria.
His mother said: "He rang at the end of August to say he was going to Syria. I was horrified. I just expressed 'do not be so stupid, don't do it, don't go there'."
The family later received an email entitled New Life in which Petty explained he had been unhappy living in the UK since he became a Muslim and he wanted to be "free to practise Islam".
He told them he had not warned them before about his plan because he thought they might try to stop him.
He wrote: "We are not just bloodthirsty terrorists. I have been training to be a soldier.
"Nobody has brainwashed me or tricked me into doing this. The whole world is united to destroy us."
On October 30, Ms Boyce contacted MI5 about his disappearance, having tried to ring the police but been unable to get though.
While in Syria, Petty had maintained contact with his family through WhatsApp but in the middle of December 2014 all communication ended.
Ms Boyce wiped away tears as she said they were not told of his death and she had to identify him later from video footage of her son's body, under the name Abu Yaqoob Britany.
The court heard that Petty was brought up in a Church of England family and went to a local secondary school.
He converted to Islam around the age of 15 and left school after doing his GCSEs, saying he wanted to travel.
He finished a hospitality course and went to Paris and Egypt for a year before studying Arabic at university.
He dropped out of the degree course and came home for a year before going travelling again.
Ms Boyce said: "He said our country was far too cold and wanted to live in warmer places and he just loved exploring. He had a year out and then went back to finish his course."
Petty went to Kenya with Moore's husband Aslam, and Omar - the brother of another jihadi called Isaiah Siadatan, who is still in Syria now.
She told jurors her son was "very good friends" with Aslam and they used to play on an Xbox together at his house.
But during their holiday, there was a falling out and they parted ways. She said: "Something happened, I don't know what but there was a falling out between Saj, Omar and Jake, and Omar and Jake had gone off but they were picked up near Somalia.
"They did not have the right papers to be there. They were deported from Kenya. He was monitored for the next year or so and there were checks every time he came back in the country."
Ayman Shaukat, 27, who allegedly helped Aslam and another jihadi, Alex Nash, on their way to Syria is on trial alongside Moore.
Moore, of Glebe Street, Walsall, denies failing to disclose information about acts of terrorism on or before August 24 2014 that might be of assistance in securing the apprehension of Aslam.
Her co-defendant Ayman Shaukat, 27, of Pargeter Street, Walsall, allegedly helped Aslam and another jihadi Alex Nash on their way to Syria..
He denies two counts of preparing for terrorist acts in relation to helping Aslam and Nash as well as possession of information contrary to the Terrorism Act 2000 in relation to a copy of "39 Ways To Serve And Participate In Jihad" on a laptop external hard drive.