Bursting with pride, the 49-year-old TV star shared a series of clips on his Instagram Stories documenting Junior's milestone achievement.
WATCH: Peter showered Junior with support
From a VIP vantage point, Peter filmed Junior, 17, while he put on an energetic performance of his latest single Slide. In the background, a throng of crowds could be seen swaying from side to side using their phone torches as mini light beacons.
Dressed for his big moment, Junior donned a black Palm Angels tracksuit which he teamed with a white T-shirt, a pair of grey trainers and a gold link chain.
Junior posed with his fans
At one point, a string of flares illuminated the stage before Junior was then showered in colourful confetti.
Peter captioned his post: "Beyond proud of your first ever gig son. So much more to come…". He followed this up by adding: "Show: smashed, eardrums: burst, post-show maccies: munched."
The singer is following in his father's footsteps
This isn't the first time the Mysterious Girl hitmaker has gushed about his children's talents. Earlier this month, Peter shared an impressive video of his five-year-old son, Theo, shooting a basketball into a free-standing hoop. Sharing the adorable clip with his 1.8 million followers, Peter captioned his video: "Yes Theo", alongside a red heart emoji.
As well as little Theo, Peter and his wife Emily are also proud parents to eight-year-old daughter Amelia. In addition to this, Peter shares Princess, 15, and Junior, 17, with his former wife Katie Price.
Emily and Peter are proud parents to Amelia and Theo
Peter and Emily tied the knot on 11 July 2015 with an intimate Devonshire ceremony. The pair first met in 2010 after Peter was treated for kidney stones by Emily's father and went public with their romance two years later.
The couple revealed they were expecting their first child together in 2013, and Peter popped the question just a few days before Emily gave birth.
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