Steven, now 21, from Kenilworth, Warwickshire was placed in a chemically-induced coma following the crash. Doctors said he would never recover, but his dad begged doctors to reconsider and enlisted private GP Julia Piper to examine him again after being convinced that their son could recover.
Doctors at University Hospital in Coventry agreed to let a neurologist re-examine him and, astonishingly, he detected faint brain waves indicating Steven had a slim chance of making a recovery.
Steven was brought out of his coma and he has stunned doctors by making a full recovery. In fact, Steven was discharged from hospital just five weeks later.
"My impression is maybe the hospital weren't very happy that my father wanted a second opinion. I think the doctors wanted to give me three days on the life support machine and the following day they said they wanted to turn it off.
I think if my dad would've agreed with them then it would've been off in seconds. If my parents hadn't asked for the second opinion, and if Julia hadn't been there, I wouldn't be here today.
Steven says he is determined not to dwell on the past, and the car accident that killed his friend, caused by a collision with two other cars and a loose horse.
"As far as I am concerned, living is a full recovery. From how I was to how I am now, I think it's a miracle. I drive to work every day, I don't think anything is holding me back. There's no point dwelling on it, I just pull my socks up and get on with it.
'Hopefully it can help people see that you should never give up. I've had so much positive feedback about it. If you believe it then follow it, that's the motto. My father believed I was alive - and he was correct.
"It's hard for me to even ask my parents about what happened. They do cooperate with me because they want me to understand it all but they don't want to be reminded about it."
Dr Piper, who runs a private practice in Leicester, said: "They had doctors saying he wasn't going to live but the parents felt there was flickers of response and it wasn't just wishful thinking.
I had this strong feeling that this wasn't right and then eventually I got someone else to look at him and of course it proved to have been the right thing to have done. It's an inspirational story about never giving up. He's a remarkable young man and his recovery has been astonishing.
Since waking from his coma, Steven has had four operations to reconstruct his face - including having his nose rebuilt and an artificial eye socket made. He also has physiotherapy session to improve the movement in his left arm, which was badly injured in the road smash.
In a statement, University Hospitals Coventry and Warwickshire NHS Trust said: 'The injury to Steven's brain was extremely critical and several CT scans of the head showed almost irreversible damage. It is extremely rare that a patient having suffered such extensive trauma to the brain should survive.
"However, critical care and other specialist teams continued to support his systems through his critical period and we were delighted to see Steven recover and make progress against all the odds.
"He is truly a unique case."
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