The prince, who turned 2 on July 22, has been telling people he's actually 3, mom Princess Kate revealed Sunday.
Kate made the revelation as she met 2-year-old Freddie Wilson, who introduced himself to her at Land Rover Ben Ainslie Racing's headquarters in Portsmouth, England.
"Hello Princess, my name is Freddie Wilson," he boldly said to her.
His mother Wendy Maxwell told reporters, "She asked him how old he was and he said 'I'm 3'.
"When I said he is only 2, she said, 'George says that. He thinks that he's older.'"
Kate also spoke with 2-year-old George Mills and his 13-week-old brother Harry, who had fallen asleep.
The couple was also given gifts for George and Princess Charlotte – two BAR shirts with the little prince and princess's names printed on the back, which were made by sisters Ella Morgan, 13, and Millie Morgan, 11. Ella and Millie's mom, Jo Grindley, serves as the team's commercial director and told reporters that the duchess had said the tops were "cute."
Their mother Rebecca said, "She asked George if he likes Peppa Pig and said she hoped Charlotte would be doing a lot of sleeping too."
Earlier Kate had had another go on a sailing simulator as she and Prince William joined Sir Ben Ainslie on a tour of the center.
She joined the Olympic hero alongside a ship's wheel and donned a pair of virtual reality goggles with him to try out the "virtual sailing experience."
Details of how the simulator operates are shrouded in secrecy, and although it does not move, users get the feeling of being on deck in an ocean boat race.
Staff warned Kate that she could stop if she felt sick and she was heard describing the sensation as "weird," but seemed well able to cope with the experience, which for her visit was set to replicate being on the sea in 15 knot winds. (She is a keen sailor, after all.)
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There were shown a big screen where the team can view and replay footage from training sessions and Sir Ben joked: "The only issue with this is that it gets all the audio off the boat."
William asked: "Lots of bleeps then?"
Sir Ben laughed and replied: "If someone's having a bad day at the office you hear it all." The royal couple also met the aerodynamics team and quizzed them about the different sails used.
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