Pink Floyd rocker David Gilmour was in court in London on Wednesday to watch as his son appealed against his "harsh" prison sentence for violent disorder during student protests last December.
Charlie Gilmour is currently serving a 16-month stint behind bars after he was caught on camera causing havoc in the capital as part of a demonstration over a huge hike in university tuition fees.
His antics included swinging from a flag on the Cenotaph war memorial and urging fellow protesters to "storm Parliament."
The 21 year old is now fighting the sentence, with his lawyer telling the Court of Appeal that Gilmour was aware of the "significance" of the monument, but had not realised he was dangling from a war memorial.
Judges were also told by defence QC, David Spens, how Gilmour had taken psychedelic drug LSD prior to the protests, but argued the student had "successfully reformed and rehabilitated himself" and addressed his "underlying drug and alcohol problems," adding, "My submission is that this sentence was unduly harsh, unnecessarily so."
Judges are expected to make a decision on Gilmour's appeal application next week.