Princess Beatrice recently announced her engagement to Edoardo Mapelli Mozzi, and they are set to tie the knot in 2020. As another royal wedding is about to happen, it is expected the royal family member attendees and the bride herself to follow the royal tradition. So, what do the Princess of York, Kate Middleton, and Meghan Markle have to do in the event constrained by a lot of royal protocols?

According to Express, there is a strict dress code that the royals have to follow whenever there is a royal wedding. Hence, the royal family members must be cautious when choosing what to wear in a big event like this.

Royal journalist Camilla Tominey said on This Morning that the likes of Meghan Markle and Kate Middleton needed to follow strict rules when attending royal weddings. "We'll have to keep an eye on Kate and Meghan because traditionally they wear outfits they have already worn before," she said.

When asked if the re-wearing dress was a royal tradition, she answered yes and explained that it is for a simple reason not to "upstage the bride." The attention should be on the bride and not on Kate Middleton or Meghan Markle.

In fact, Kate Middleton followed this rule when she attended Meghan Markle's wedding in 2018. At the time, she wore an Alexander McQueen yellow coat, which she already donned a few times before, like at Princess Charlotte's christening, Trooping the Color in 2016, and a visit to Belgium in 2017.

Meghan Markle also obeyed this rule when she opted for an oversized dark navy coat at Princess Eugenie's wedding last year. Princess Beatrice has yet to announce additional details about the wedding, but her father, Prince Andrew, said that there would be information given in due time.

Meanwhile, the bride herself also has a royal tradition to follow on her wedding day. Royal brides often choose to carry a sprig of myrtle in their wedding bouquets. This tradition dates back to the wedding of Queen Victoria in 1840.

They also have to lay their bridal bouquet on the Tomb of the Unknown Warrior. It is a nearly 100-year-old tradition established by Lady Elizabeth Bowes-Lyon, a.k.a. Queen Elizabeth, the Queen Mother, who laid her wedding bouquet at the British grave in memory of her brother, Fergus, and to honor other armed forces who died in World War I.

The newly-weds also have to have their official wedding photographs. King Edward VII and Queen Alexandra started this tradition in 1863 at St George's Chapel. In the 20th century, postcards featured royal weddings to share the royal event to the public.

Lastly, Queen Victoria also started the use of orange blossom tradition. She chose not to wear a tiara on her wedding, but a wreath of orange blossom as a sign of purity.