The Duchess of York recalled what a "magical day" the wedding of Princess Eugenie and Jack Brooksbank was in a moving Instagram post marking the couple's third wedding anniversary. In her poignant message Sarah, who took to her social media account on the evening of October 12, also let slip a sweet moniker for her daughter.

       She wrote: "Happy Wedding Anniversary, what a magical day.

       "Thank you, Jack and Eugie for sharing your hearts.."

       The Duchess included in the post a picture taken at the end of Eugenie and Jack's wedding ceremony.

       It depicts the happy couple walking down the stairs outside St George's Chapel.

       They are followed by their page boys and bridesmaid, including Prince George and Princess Charlotte, and their close relatives.

       Sarah can be seen beaming at the newlyweds in her vibrant emerald green dress by Windsor designer Emma Louise Design.

       The Duchess shared this tribute to her daughter hours after Eugenie had marked her own anniversary by publishing a never-before-seen picture taken during the wedding party.

       In the snap, she can be seen smiling at the camera while dancing with her new husband Jack.

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       While she got married in a stunning Peter Pilotto gown which showed the scar on her back, Eugenie donned a blush pink Zac Posen dress during her wedding reception.

       The princess wrote in the caption: "Happy Anniversary my love.. three years today!!"

       Jack and Eugenie got married at the same chapel which, between 2018 and 2019, hosted two more royal weddings - Meghan Markle and Prince Harry's and Lady Gabriella Windsor's.

       On February 9, Eugenie gave birth to her first son, August Philip Hawke, whose names pay tribute to both his maternal and paternal relatives.

       Eugenie has since marked special occasions, including Jack's birthday and Mother's Day, by posting on Instagram pictures of her baby.

       Sarah became a grandmother twice this year, as her elder daughter Princess Beatrice has also recently given birth.

       Beatrice and her husband Edoardo Mapelli Mozzi welcomed their first daughter together, Sienna Elizabeth, on September 18.

       The couple has decided not to share a picture of their baby yet.

       However, upon revealing their daughter's name on October 1, they also released a snap showing Sienna's footprints taken on the day of her birth.

       Neither August nor Sienna have a royal title but they have both been included in the line of succession to the throne.

       August currently sits in the 13th position while Sienna follows her mother and is 11th-in-line to the throne.

       Sarah has voiced multiple times her pride and happiness for her daughters' lives and families.

       Most recently, just days before the birth of Sienna, she penned a letter published by Good Housekeeping, in which she expressed her joy saying: "It is an extraordinary feeling when your child becomes a mother.

       "Suddenly my little girlies have their own little ones ... such a feeling to get used to.

       "But if I do cry or tear up as you drive away, it is only because I am so proud of you.

       "It has been just us for 33 years, but now you are creating your own families, and I couldn’t be happier for you both and my magnificent sons-in-law, Jack and Edo."