18-year-old Tiernan McMahon remained in a critical condition in hospital on Saturday morning, as two men appeared in court, charged with attacking him and his uncle, John Paul McMahon, at the New Lodge bonfire in north Belfast.
Caolan Donnelly, 21, and 28-year-old cousin Francis Donnelly, were remanded in custody at Belfast Magistrates' Court.
The attack happened as large crowds gathered to watch the bonfire, which marked the anniversary of the introduction of a controversial policy of internment without trial of suspected republicans in 1971.
The police had to abandon an operation to remove the structure before it was lit, after violent clashes saw three officers injured.
A police officer told the court that John Paul McMahon, 39, was attacked in the early hours of Friday morning at the illegal bonfire, in an incident allegedly linked to a year-old dispute between him and other men.
He suffered non-life-threatening injuries to his arm and hip.
The officer said that Tiernan McMahon sustained more serious injuries during the attack.
"He stepped in and was trying to help when he was attacked, put to the ground and was stabbed a number of times in the back," he said.
The officer added that Tiernan McMahon suffered a collapsed lung which required two blood transfusions, and back wounds that needed five staples.
Caolan Donnelly has been charged with two counts of grievous bodily harm with intent and two counts of possession of an offensive weapon with intent to commit an indictable offence.
His lawyer did not make a bail application and he was remanded in custody by the judge.
Francis Donnelly appeared in the dock just minutes earlier and made an unsuccessful application for bail, as he faced two counts of GBH with intent, possession of an offensive weapon with intent to commit an indictable offence and possession of an offensive weapon in a public place.
Both men were remanded in custody and will appear before the same court via video link next month.