The Princess wrote: “Thank you for the birthday love yesterday… I got the best present I could ask for!!”
The post was accompanied by two new photos, one of which showed a beaming Eugenie holding August in her arms while looking at proud dad Jack.
In the picture, August is wearing a white baby beany and adorable knitted cardigan emblazoned with his name on the back.
The second photo shows little August peering at the camera over his father’s shoulder.
Eugenie gave birth to August Philip Hawke on February 9 and has been settling into motherhood at Frogmore Cottage in Windsor ever since.
The residence is on loan to the couple from Prince Harry and Meghan Markle, who are now based in the USA full-time.
Frogmore Cottage is just up the road from Eugenie’s parents, Sarah Ferguson and Prince Andrew, who are said to be in a bubble with their daughter.
The doting grandparents are understood to be lending a hand with childcare as Jack and Eugenie settle into life as parents.
Given that Eugenie is in a bubble with her parents, it seems possible the new pictures were taken by her mother Sarah Ferguson, who shared her joy at becoming a grandmother following August’s birth.
Fergie paid tribute to Eugenie on Instagram to mark her birthday on March 23.
The Duchess posted a throwback snap of herself with a young Eugenie.
The retro photo was accompanied by the message: “The joy of children. In deep gratitude for my luck in my glorious girls. Happy Birthday Eugenie…”
Eugenie shared the intimate family snaps on the same day the Royal Family celebrated more baby news, after it was confirmed Zara Tindall, 39, and husband Mike welcomed a baby boy, Lucas, to the world on Sunday.
Like Eugenie and Jack, the Tindall’s have given their son the middle name Philip in a touching nod to his great-grandfather Prince Philip, 99.
Princess Eugenie’s son is 11th in line to the throne and the Queen and Philip’s 9th great-grandchildren.
While the Queen is just up the road from Eugenie at Windsor Castle, she is unlikely to have met him yet due to COVID-19 restrictions.
Royal fans were overjoyed by the new pictures of Baby August and rushed to congratulate Eugenie on Instagram.
One wrote: “He’s beautiful”, followed by a red heart emoji.
Another put: “Happy for you and your family! God bless you.”
A third chimed in: “Omg these pictures are adorable I hope you had a great day with them.”
While dozens of other followers responded to the post with heart emojis.
Source: EXPRESS CO UK