Harry Dunn's dad said he "struggled to breathe" at the thought of coming face-to-face with his son's killer, as the teenager's parents opened up on American television since their fight for justice ended.
Tim Dunn and Charlotte Charles appeared in the US for the first time since Anne Sacoolas admitted causing the death of the 19-year-old as she left an airbase in Northamptonshire in 2019.
Speaking on CBS Mornings, the parents told presenter Gayle King they were "completely shocked" when the judge in the hearing ordered the US intelligence worker to return to Britain to hear her sentence in person next month.
"I wasn't expecting that," said Mr Dunn. "It was shock and disbelief. I struggled to breathe. It was amazing and scary. I didn't think I would ever meet this lady, to be honest."
Sacoolas fled the country 19 days after the crash that killed Mr Dunn outside RAF Croughton after diplomatic immunity was asserted on her behalf by the US government.
Despite protracted negotiations, the US authorities repeatedly refused to extradite Sacoolas so she could face trial.
When the case finally came to court three years later, the parents agreed to the driver appearing remotely so she could remain in the US with her own family.
Asked whether he wanted to meet his son's killer, Mr Dunn said: "I don't know how to answer that. I suppose I should, but whether I could actually do it and keep my emotions in, I don't know."
During Thursday's hearing at the Old Bailey, judge Mrs Justice Cheema-Grubb told Sacoolas that "attendance [at sentencing] would provide weighty evidence indeed of genuine remorse” but admitted she had no powers to force her.
The driver admitted causing death by careless driver which carries a maximum five years in prison but can be dealt with by a community order.
Ms Charles said the family had never wanted the US citizen, who is a mother to three children, to go to jail and they would be happy for her to return to America as soon as she was sentenced.
But she said she needed Sacoolas "to take the accountability" and finally get some justice for Harry.
She thanked the American public and media for their support "from the bottom of our still-broken hearts".
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