The rugby star’s gruelling mission will end on Saturday at Old Trafford in Manchester, when Sir Kevin arrives ahead of the Super League Grand Final.
“Make sure you hold yourself together for another few days,” Prince William told him.
Sir Kevin replied that he had been dreaming of an ice bath all day.
Since his first challenge in 2020, Sir Kevin has raised more than £11m for MND causes – and Prince William and Catherine made a private donation to the charity effort.
Before meeting Sir Kevin, the royal couple talked to families facing the impact of MND and heard how fundraising projects had helped them.
Earlier on Tuesday, Prince William and Catherine visited the home ground of Rob Burrow’s rugby league team, Leeds Rhinos, and met some young players.
The royal visitors heard how the club’s charitable foundation was working to help health, education and well-being projects in the Leeds area.
Jamie Jones-Buchanan, a former teammate of Rob Burrow, described the team’s ethos in good and bad times: “We went through success and adversity, but we always came out on the other side together.”
