The royal family Instagram account is getting ahead of the festivities and just shared Duchess Sophie's portrait before her birthday on Monday. However, there's one tiny detail that I almost missed—and it has nothing to do with her photos.

It’s a milestone birthday for Duchess Sophie, who officially rang in the special day on January 20 with a little more pomp and circumstance than usual, courtesy of an official new portrait and plans for a major birthday celebration at their Berkshire home Bagshot Park.

The royal family has wished the Duchess of Edinburgh a very happy 60th birthday. Sophie’s milestone was celebrated on the British monarchy’s official social media accounts with a video montage of photographs of the duchess on royal engagements,

I love how she is not afraid to try new things and she makes beautiful choices,” designer Suzannah Crabb of royal favorite Suzannah London tells PEOPLE

Sophie, the Duchess of Edinburgh is turning 60 in style. The royal—who marked her milestone birthday on Monday, January 20—released a trio of stunning portraits to commemorate the special occasion over the weekend that seemingly included a subtle sartorial nod to her grand new title.