Queen Mary and King Frederik of Denmark are, without a doubt, one of the favourite couples among royal fans, thanks to their close-knit relationship and deep commitment to their roles. Today marks the royal couple's 21st wedding anniversary, but, as anticipated from such dedicated monarchs, the pair has been forced to spend this important day apart due to their respective duties. Queen Mary is expected to hold a meeting at the Mary Foundation, a charity founded in 2007 by the Danish royal herself to tackle issues close to her heart, including bullying, domestic violence and loneliness. The Queen’s devotion to the charity is much more than that of a simple patronage, as she very often is on the front line of its campaigns and projects. During one of her poignant speeches last month, her Royal Highness said: "Violence is never the children's fault. It is our, the adults, responsibility to see, to reach out, to ask and to act. We have to do it for the sake of each child. And we have to do it for each other." While Queen Mary will be at the Mary Foundation, King Frederik is going to present the Danish Academy of Science’s gold medal to this year’s recipient as one of the institution’s patrons. Queen Mary and King Frederik's love story The couple got married on this day in 2004, in Copenhagen Cathedral. The now King and Queen met in Sydney, where a young Prince Frederik was visiting during the Olympics. There, in a pub, he met an advertising executive from Tasmania, Mary Donaldson, and their fairytale romance soon began. They started dating in 2000, Queen Margarethe gave her blessing to their union in 2003, and the rest is history. Of that very special day, 20 years ago, royal fans will remember the chanting crowd, ecstatic at the sight of their new future Queen, waving at them from the balcony of Amalienborg Palace. But who could forget the stunning dress worn by the Australian-British young woman turned Danish Princess? The royal, also known as Countess of Monpezat, wore an ivory duchesse satin gown by Danish fashion designer Uffe Frank with an Irish-lace veil, previously worn by Crown Princess Margareta of Sweden, pinned to a diamond tiara, courtesy of Queen Margrethe II. To honour her family’s Scottish heritage, her father, mathematician John Donaldson, wore a traditional kilt and looked proud walking his daughter down the aisle. John wasn’t the only one overcome with emotion on that day. The then Crown Prince of Denmark was photographed crying tears of joy as his new bride made her way to him in the church. The couple now has four children, Crown Prince Christian, Princess Isabella, Prince Vincent and Princess Josephine, and still appear as happy and in love as ever. We hope they will have time for a well-deserved celebration, after all.