The Duke of Cambridge joined presenter Nick Knowles and the team for the TV special on Wednesday night, as they worked to build a new boxing academy to replace the original Dale Youth Club, lost in the fire last June.
The future king and brother Prince Harry have previously appeared on the BBC programme, back in 2015, when they helped the team to rebuild homes for ex Army service men and women.
William rolled up his sleeves once again, to paint a wall on the site of the new centre to help restore it to its former glory.
The amateur boxing club has been credited with turning round the lives of many young people. The original was on the first floor of the Grenfell Tower and since the blaze, it has had a temporary venue.
During the visit, William met with 14-year-old boxer Jodie, who lost a friend in the fire, and gave him some advice on how to cope with grief and loss.
The prince – who lost his mother when he was 15 – told the teen: “It’s a horrible process to have to go through but you’ve got the right people around you and I hope you talk about it.”
“It’s ok to take about how much you miss your friend. That’s perfectly normal.”
William also urged Jodie to “keep boxing as well. I can see that twinkle in his eyes.”
The Grenfell fire broke out in the early hours of June 14, 2017, claiming the lives of 72 people and leaving hundreds homeless.
William and the Queen visited victims near the site, just days after the tragedy.
The DIY SOS: Grenfell special is a two-part series and will continue next Wednesday, September 12, which will show the rebuild of the community centre.
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