A teenage driver died after crashing into a lorry when he fell asleep for a matter of seconds.
Joe Andrews, 19, caused the accident when he had what's known as a 'microsleep' – where the eyes can stay open even though consciousness is lost for up to 30 seconds.
Joe was on the road at 5am after watching the sunrise with his girlfriend, Allanah Salton, 17, who was injured in the accident.
Both Joe and the lorry driver were well under the 40 mph limit when the tragedy occurred.
Joe's heartbroken mum Julie, 49, told her local paper: "We are having really good weather this summer and it was good weather when Joseph had his accident.
"Microsleep caused Joseph's accident. He hadn't been drinking or taking drugs, he wasn't speeding, he wasn't smoking, he wasn't on his phone, he just had that microsleep and unfortunately his injuries were too bad for him to be saved.
"We want to raise awareness about microsleep, particularly among young people who are finishing college or university for the summer. They stay up all night on social media, gaming, talking to friends and trying to fit so much in.
"We want to explain from the parents' point of view and warn about the hazard we don't see, you don't think of tiredness.
"I never wanted to be a 'what if mother' but I am.
"You think if only the car had been five minutes earlier or later Joseph would have rolled into the verge and he would have phoned and said I've damaged my car, and it would not have damaged him like it did.
"We've lost our only child, we have lost our life. It rips your world apart.
"It was that one little second that changed our lives forever. All our hopes and dreams have gone with him."
Mr Andrews, 50, said: "The kids have just had all the pressure lifted off them at the end of their exams.
"You see them on Facebook up at goodness knows what time and a lot of them are mobile with mopeds and cars.
"As parents you drum into your kids about drink and drugs but you don't think of this microsleep, sleep deprivation. We want them to be aware of this danger.
"It's happened to all of us. How many times have you nodded off in front of the TV? You can rewind a TV programme, we can't rewind what happened to Joseph.
"You can't decide when it happens, your brain shuts down and your eyes can be open.
"This message is for kids who still have the summer in front of them. We don't want other parents to feel like we do, or girlfriends and boyfriends to feel like Allanah does. One second can change your life."
Joe's girlfriend Allanah said: "Everyone thinks it won't happen to you. Just think about everyone involved.
"Some people still think Joe had been speeding but he hadn't. He was sensible and a good driver."