Thomas had been talking on his mobile phone when he was punched in the face in an unprovoked attack and fell backwards, hitting his head on the ground, police said. Thomas Kelly ... his "life was finally taking off" when he was fatally punched in an unprovoked attack. His attacker fled and Thomas was taken to hospital in a critical condition with head injuries. He died at 8pm yesterday. Police do not believe robbery was a motive as Thomas's iPhone and wallet were left untouched. Police also do not believe there was any altercation between the two men. Thomas's parents today made a public appeal for assistance in solving the crime. His father, Ralph Kelly, said his son was "one of the most courageous boys I've ever met", having had a difficult time at school.

But, he said, his son's "life was finally taking off" after he got a cadetship with a Sydney accounting firm. Appeal ... grieving parents Kathy and Ralph Kelly at today's briefing. Credit:Steve Christo Mr Kelly said his son had met a girl just four weeks ago after never having had a girlfriend before. "We're sitting here today, on behalf of our son, to appeal to the public to please come forward with any information," said Thomas's father Ralph Kelly. "We can't even remember what day it is, we haven't changed our clothes since we came up from Bowral ... is like being in a hole... We know it's going to be a massive, massive hole for us." A picture of Thomas lies by the hand of his distraught mother during today's briefing. Credit:Steve Christo

Mr Kelly said he and his wife had driven from Bowral after being told Thomas was in hospital. He had finally got to see Thomas at 3.30am on Sunday. Mr Kelly said he had asked Thomas not to go to Kings Cross, "but you can't tell an 18-year-old what to do". I'm assuming this person must have been either drunk or drugged ... he knew he intended to punch our son ... he was out to hurt people He said his son had only been in the nightclub precinct for a matter of minutes when he was punched. "The last words that both [his mother] Kathy and I said to him was 'Please be careful, please take care.'

"He said: 'I will and I love you.' "And that's the last time we spoke to him." He said the family had donated Thomas's organs because they "felt his death should result in some life for other people". Thomas's mother said she could say with certainly that "there was no way Thomas would be drunk". Mrs Kelly said she understood he "had been holding his little girlfriend's hand, whom he had just met, and she was holding the other girl's hand".

Mrs Kelly understood that the attacker had stepped out past the two girls and stood in front of Thomas and punched him. "I'm assuming this person must have been either drunk or drugged ... he knew he intended to punch our son ... he was out to hurt people." She said the family had to live with this for the rest of their lives and she appealed to the attacker: "If you have any remorse you need to come forward if you are to have a life." Thomas worked as an accounting cadet in the city during the week and studied commerce at Macquarie University at nights. He and his father lived in his father's office during the week and on weekends they would return to the family home in Bowral.

The mother of one of the accounting cadets said her son was devastated by Thomas's death. "You just feel as a mother when your son is really upset. He was pretty devastated and couldn't believe what happened," Anne, who did not give her last name, said. "He was just a kid. He was just so excited about going out ... to the 18th birthday party." Anyone with information is asked to phone Crime Stoppers on 1800 333 000. smh.com.au, Nick Ralston, AAP and Glenda Kwek

