Kate Middleton, 39, released an adorable picture of the future king on the Cambridges’ Instagram account to celebrate the occasion.
This picture was taken in the Cambridges’ Anmer Hall home in Norfolk, and Prince George looked extremely happy, grinning ear to ear to have his picture taken.
One fan wrote, “What a lovely photo as always from the Duchess, George is looking so grown up!”
Another commented, “Oh my goodness look how much he resembles his dad and his grandmother.
“Happy Birthday, young Prince!”
The t-shirt Prince George is wearing is made from 100 percent cotton shirt and costs between £8 and £12, depending on the size.
George is wearing a sized eight meaning his only costs £10, which for a Royal Family member is a very frugal choice.
It is framed by a classic polo collar and features three buttons down from the top.
Since the photo of Prince George was released, the t-shirt became sold out on the John Lewis website.
A celebration for the prince will be held today in Kensington Palace but no formal details have yet been released.
Kate Middleton spoke to Mary Berry about baking cakes for her children’s birthdays on the BBC’s A Berry Royal Christmas.
She said: “I love making the cake. It’s become a bit of a tradition that I stay up until midnight with ridiculous amounts of cake mix and icing.”
Royal watchers have seen Prince George grow up in front of their eyes and many cannot believe he has already turned eight years old.
He is currently third-in-line to the throne, after his grandfather Prince Charles, 72, and his father Prince William, 39.
When he is crowned king he will be styled King George VIII.
Today the eight-year-old can relax with his family at Kensington Palace as royal watchers hope the Duchess will share more charming snaps of the birthday prince over the next few days.