Prince Harry was told he would be the best uncle in the world after being presented with a mini jumpsuit for Prince George at the Boultbee Flight Academy.
The prince was at Goodwood, West Sussex, to launch the Spitfire Flight Scholarship, for wounded ex-servicemen as part of The Endeavour Fund, which gives grants to projects to help get them off the ground.
John Laity, expedition co-founder for Flight For Freedom, which is part of the Royal Foundation of The Duke and Duchess of Cambridge and Prince Harry, which created The Endeavour Fund, gave the prince the jumpsuit for his nephew.
He said the prince asked him whether it was the real thing or a onesie.
The prince also spent the morning racing classic cars alongside injured servicemen who have benefited from the charity set up to help them rediscover their self-belief and fighting spirit.
He smiled as he sped around Goodwood Motor Circuit in a 1964 two-series blue Aston Martin DB4, a black Lamborghini, a silver Aston Martin and a red Jaguar, a prototype F-type Coupe R.
Harry, who is patron of the Royal Foundation of The Duke and Duchess of Cambridge and Prince Harry, spoke to soldiers supported by The Endeavour Fund, which plays an important role in ensuring that more wounded, injured and sick servicemen and women have the opportunity to rediscover themselves through physical challenges.
So far, The Endeavour Fund has supported more than 300 men and women through projects including the Walking With The Wounded trek to the South Pole, Race2Recovery, Walk On Wales, Flying For Freedom and a Fastnet Race team.
Captain Mark Jenkins was part of a team of four who took part in Row2Recovery, sailing from the Canary Islands to Antigua in the Talisker Whisky Atlantic Challenge.
The 34-year-old, who is part of the Royal Army Medical Corp, was joined by amputees, soldiers Cayle Royce and Scott Blaney, and fellow serviceman James Kayll.
He said the project would not have been possible without a £30,000 grant from The Endeavour Fund.
Capt Jenkins said they received the funds after going through a "Dragons Den-style" presentation.
He said: "It's the best thing you have ever done, the hardest thing you have ever done, the worst thing you have ever done, all in one experience. It's hard to mentally and physically motivate yourself to keep going."
Mr Jenkins said the scariest moments were when their boat capsized and getting a bit too close to a few ocean liners for comfort.
He said the team were hoping to raise £100,000.
David Wiseman, who was a captain in the Yorkshire Regiment, joined The Endeavour Fund last year after taking part in challenges for Walk with the Wounded.
The 31-year-old, who was shot in the chest in Afghanistan, climbed Manaslu, in Nepal, the eighth highest mountain in the world, in 2011, and attempted Everest in 2012.
He said he joined the Fund because he knew the power challenges like this could harness in people who have been injured.
RAF Corporal Alan Robinson, 35, who is involved with Flying For Freedom, spoke to the prince about how the Fund has helped to train servicemen to become microlight pilots.
His aim is to fly a microlight to the Antarctic, he said.