McNeil had been charged with maliciously inflict grievous bodily harm and assault occasioning actual bodily harm following the alleged New Year's Eve assault but the charges were upgraded by police on Monday afternoon.

Daniel died on Saturday after spending 11 days on life support in St Vincent's Hospital with severe brain injuries.

Police allege McNeil punched three underage boys on the corner of Victoria Street and Darlinghurst Road at Kings Cross around 9pm on New Year's Eve after the boys allegedly approached Mr McNeil and his girlfriend about buying drugs.

One of the boys ran away but the other two hid behind Daniel Christie and his brother Peter, who were walking down Victoria Street on their way out to a nightclub.

Mr McNeil allegedly punched Daniel once with a closed first to the side of the head, causing him to fall onto the pavement and smash his head.

Peter tried to throw himself between his brother and Mr McNeil and was also allegedly punched, sustaining a cut lip.

Mr McNeil has been charged with four counts of assault over the alleged attacks on Peter and the three juveniles.

He will face Central Local Court on Tuesday on the charge of murder.

Following the 18-year-old’s death, NSW Attorney-General Greg Smith on Saturday said he had asked the Director of Public Prosecutions to consider whether a murder charge was more appropriate.

Mr Christie’s family released a statement shortly after his death, describing him as a ‘‘beacon of morality’’.

‘‘His death has left us feeling completely destroyed and has torn a hole in the wider community in which he was involved,’’ they said.

‘‘No family should be forced to deal with this situation, however we are not the first and we fear that we won’t be the last.’’

Mr Christie was punched in almost the same location as 18-year-old Thomas Kelly was fatally struck by one punch in July 2012.

Both attacks have prompted growing calls for tougher sentencing for alcohol-related violence.

- with AAP

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