The Subtle Way Kate Middleton Honored Princess Diana

Kate Middleton is getting ready to release her first book titled Hold Still: A Portrait of Our Nation in 2020, which is slated for release on May 7, 2021, according to the Kensington Royal Instagram account. The book is an extension of the Duchess of Cambridge's Hold Still photography project, which was announced in 2020. "'Hold Still' aims to capture a portrait of the nation, the spirit of the nation, what everyone is going through at this time. Photographs reflecting resilience, bravery, kindness — all those things that people are experiencing," Kate previously said in a statement, according to Town & Country. 

While the new photography book captures a unique time in the lives of millions of people across the globe, profits from its sales are also going to support a good cause. "Funds raised from the sale of the book will be split between leading mental health charity, Mind, and the National Portrait Gallery," according to the Duke and Duchess of Cambridge's Instagram update. In a subsequent Instagram post, Kate actually added a subtle nod to Princess Diana, her husband's late mother, according to Us Weekly. 

In a new promo for her new book, Kate Middleton penned a personal message to accompany a new photo of herself — and it included a nod to Princess Diana! "I wanted to use the power of photography to create a lasting record of what we were all experiencing — to capture individuals' stories and document significant moments for families and communities as we lived through the pandemic," Kate captioned the Instagram post, signing the message with a "C" for Catherine. 

In the snap, Kate is wearing a dark red sweater over a white shirt that features a neck ruffle. According to Us Weekly, it's that neck ruffle that is significant. The "pie crust collar," as it's called, "initially got its claim to fame from Princess Diana, who wore a white collared shirt on numerous occasions. She typically styled the ruffled neckline under coats, sweaters or even rocked the rushed neckline solo," the outlet reported. Of course, this isn't the first time that Kate has honored Diana by way of an outfit choice or a piece of jewelry — and it most certainly won't be the last.