Royals Sarah Ferguson Celebrates Princess Eugenie's Birthday with Throwback Pic: 'My Magical Beloved Daughter' The Duchess of York recently told PEOPLE that she and her daughters, Princess Eugenie and Princess Beatrice, call themselves "the Tripod" By Janine Henni Janine Henni Twitter Janine Henni is a Royals Staff Writer for PEOPLE Digital, covering modern monarchies and the world's most famous families. Like Queen Elizabeth, she loves horses and a great tiara moment. People Editorial Guidelines Published on March 23, 2023 11:28 AM Share Tweet Pin Email Photo: Sarah Ferguson instagram Sarah Ferguson is thinking of Princess Eugenie on her birthday. On Thursday, Eugenie's 33rd birthday, the Duchess of York, 63, celebrated her youngest daughter with a loving Instagram tribute starring a throwback photo. In the image, a young Princess Eugenie kept it cool in a denim jacket, sunglasses and a pink hair bow. "Happy Happiest of birthdays, my Eugenie .. Spring flowers always tells me the excitement of your birthday is soon and here we are. You are my magical beloved daughter and I am so proud of you," Fergie, as the Duchess of York is affectionately known, captioned the photo. A proud mother of two, Ferguson shares daughters Princess Eugenie and Princess Beatrice with ex-husband Prince Andrew. The princesses are both close with their mom, who recently told PEOPLE that they call themselves "the Tripod." Happy Birthday, Princess Eugenie! 15 of the Relatable Royal's Most Candid Moments on Instagram Opening up about her "granny" era, the Duchess voiced her joy in seeing her daughters as parents today. Princess Beatrice, 34, is mom to 1-year-old daughter Sienna Elizabeth and is a stepmother to husband Edoardo Mapelli Mozzi's son Wolfie from a previous relationship, while Eugenie welcomed son August in Feb. 2021 and is currently expecting her second child with her husband, Jack Brooksbank. "One, I'm really proud of my girls. Two, I have very good grandchildren. Three, the most important thing is that you really focus on turning to joy," the Duchess told PEOPLE of life lately. Sarah Ferguson. Zoe McConnell Sarah Ferguson Recalls When She and Princess Diana Were Arrested at Her Bachelorette Party Mother's Day was celebrated in the U.K. on Sunday, and the author of the new novel A Most Intriguing Lady shouted out Eugenie and Beatrice in a sweet social media tribute, sharing a childhood shot of her daughters having a matching fashion moment. "I'm so proud of my girls and the beautiful women and mothers they have grown up to be. I feel extremely blessed to call them mine. My darlings, you are my sunshine always & forever," she wrote of the photo, where the sisters walked in sync. Princess Eugenie also marked Mothering Sunday, as the holiday is known in the U.K., with an Instagram tribute to her son, 2-year-old August. Can't get enough of PEOPLE's Royals coverage? Sign up for our free Royals newsletter to get the latest updates on Kate Middleton, Meghan Markle and more! "I love being your Mumma! Happy Mothers Day! Xx," she captioned the snap, which showed her and August holding hands in a frosty field. Princess Eugenie and Jack's family of three will become four later this year. In January, Buckingham Palace announced that Queen Elizabeth's granddaughter was pregnant with her second child, due this summer.