The Duke and Duchess of Cambridge, who celebrated Prince George's third birthday on Friday 22nd July, were attending the Portsmouth leg of the America's Cup World Series when a young fan enquired about George's birthday presents.
10-year-old Zak Kay, from St Paul's Primary School in Portsmouth, won a competition to design the trophy for the event.
When he asked what gifts Prince George received for his birthday on Friday, William said: 'I am not telling. He got too many things, he's far too spoilt.'
The dad of two also revealed that his son isn't 'into boats yet', despite being completely enamoured with aeroplanes.
It's not known what the young royal was gifted for his birthday, although he has certainly amassed some impressive presents in the past.
In 2014-15, he received 706 presents – more than any of his Royal relations – including a rocking horse, a cuddly toy wombat, a boat, a possum skin cloak, a personalised surfboard, two pairs of sheepskin boots and a bike.
He was also given a bespoke shepherd's hut - worth £18,000 and created for him by Plankbridge, a company set up with funds from the Prince's Trust - for a previous birthday.
William and wife Kate looked happy and content as they watched Sir Ben Ainslie's Land Rover BAR team compete in the America's Cup, before presenting the Olympic sailor - who just became a dad for the first time - with the trophy.
The royal couple also spoke with a group of youngsters, who had been taken out with the team ahead of the races through Sir Ben's children's sailing charity the 1851 Trust, of which Kate is the royal patron.