In case you hadn't noticed, there's been all sorts of drama with Prince William and Kate Middleton regarding the amount of time they've been using the royal helicopter to transport their family from their country home to London. You know, just normal person problems!
A quick TLDR on the matter? The Queen recently made it all kinds of clear that she doesn't want the Cambridges flying as a family unit so frequently for safety reasons, and they just "defied" her orders and did so anyway for a quick vacation. So now the Queen is "summoning" William and Kate to the palace for an awk chat.
But there's actually some royal protocol—about who can fly with whomst and at what age—that will make it literally impossible for George to fly with William in just a few years. Basically, two or more heirs to the throne aren't supposed to travel together in order to protect the monarchy, but according to The Express, Queen Elizabeth can override the rule for little kids—and has done so with Prince George in the past.
However! Once Prince George turns 12, the Queen can no longer override protocol, and he and Prince William literally won't be able to travel in a plane together—no exceptions. This is also the case for William and Prince Charles, who travel separately, as well as Charles and his mother the Queen.
Anyway, a few more details on the drama with her Majesty and the Cambridges: apparently, Wills and Kate were seen boarding a helicopter with their kids after the Queen told them not to use it so frequently, and royal expert Neil Sean said "When Prince William and Catherine return back from their short break, they will be summoned to Windsor to explain the cause of their actions."
To be a posh fly on the wall during that convo.