A Manchester City youth player wept in court as he was jailed for 16 months for killing a brother and sister while speeding in his Mercedes.
Courtney Meppen-Walter, 18, was at the wheel of his grandfather's "high-powered" Mercedes C220 saloon and doing nearly double the 30mph speed limit when he hit a Nissan Micra emerging from a side street, Manchester Crown Court heard.
The Nissan driver, Kulwant Singh, 32, from Salford, and his sister, front-seat passenger Ravel Kaur, 37, from Cheetham Hill, Manchester, were both killed.
Moments earlier, the defendant had been "jockeying" and "playing games" with a friend in a VW Golf along a nearby dual carriageway.
After the crash, a witness told police: "That's what you get when you mess around on roads."
Meppen-Walter got out of his car and tried to help the injured, waving his arms and saying: "What have I done?"
The defendant who was also the captain of the England Under-18 side and played 17 times for his country, will serve half his sentence - eight months - in custody but may be released earlier on an electronic tag.
Mr Singh's widow sat in the public gallery, with an interpreter relaying the proceedings, and wiped away tears during the hearing.
The crash victims came to the UK in 2001 to start a new life after fleeing persecution by the Taliban, the court heard.
Ms Kaur's two sons, aged 16 and 17, both back-seat passengers, were injured in the crash, which happened at the junction of Great Ducie Street and Sherborne Street in central Manchester at about 10.15pm on September 1 last year. They are now orphans after their father was killed in Afghanistan.
The defendant had one previous conviction for speeding - again doing 56mph in a 30mph zone.
Dressed in a dark suit and overcoat, Meppen-Walter was in tears as he went into the dock, before the judge entered the room, and wept throughout the proceedings and as he was jailed.
Passing sentence, Judge Martin Steiger QC jailed Meppen-Walter for 16 months on each charge, with the sentences to run concurrently.
He also banned him from driving for three years and ordered the sale of the Mercedes, with the proceeds going to the injured passengers.
Gwyn Lewis, defending, said Meppen-Walter was "truly sorry" for what he had done.
"To begin, it has to be said this type of case is one that should always be described as tragic. Tragic of course for the family, those who lost loved ones and were very badly injured.
"But also it's a tragedy for the defendant.
"He was only just 18. He became involved in a matter that only took a few seconds that will remain with him for the rest of his life.
"The incident was over in a flash. He stayed at the scene and tried to assist but it was already too late."
Mr Lewis added: "Turning to him as a person, you have a very, very young man who certainly had a promising football career. On the Under-18 international matches, he had played for England 17 times and was captain of the England Under-18 football side.
"He had a promising career with Manchester City, having twice appeared on the bench in Champions League matches.
"The probation report says he's a young man who wished he could have those 10 seconds back, but of course he can't."