Eugenie shared the picture on Instagram of August playing with a stuffed toy minion while wearing the cute blue monster costume.
In the accompanying comment for her 1.5 million followers on Sunday, the princess adds: "Wonder what they are talking about.."Royal fans were quick to respond to the post with supportive comments, with many of them saying how adorable August looked in his tiny outfit, reports the Express.
Read more on dailystar.co.uk