To celebrate her son’s fourth birthday, Princess Eugenie has posted a heartfelt tribute to August on her Instagram page in the form of a video montage.

The montage is a series of intimate pictures of Eugenie alongside her husband, Jack Brooksbank, and their young family.

In one picture, August can be seen holding a big golden balloon, in the shape of the number ‘four’. He is also seen riding a bike in the park, and going for a little swim alongside his younger brother, Ernest, one.

In a seven-word tribute, Eugenie wrote: “I love you my boy, my angel.”

Her full caption on Instagram read: “Happy birthday my darling Augie. 4 today. And what an amazing 4 years. You are so incredibly focused and inquisitive and full of adventure and speed. Can’t wait for all our adventures…so many more to come. I love you my boy, my angel.”

Fans have flocked to Eugenie’s Instagram page to wish the four-year-old a brilliant day.

One wrote: “Wishing August a very very very happy birthday. What a lovely reel, thank you for sharing.”

Another said: “Wishing you a very Happy 4th Birthday August.”

A third wrote: “Getting so big. Happy Birthday Augie.”

Another added: “Such a wonderful message from his dearest Mumma, we all send Augie a very special happy 4th Birthday.”