There are many age-old traditions the royal family must follow, including strict rules on the clothes they have to wear to formal events. One extremely important accessory is a headpiece, and royal women - including Kate Middleton and Meghan Markle - are often seen wearing hats at christenings, birthdays and weddings.
The royal ladies will be expected to wear either a hat or fascinator as they attend the Queen's funeral on Monday 19 September, to pay their respects to the late monarch and honour the longstanding tradition. Queen Consort Camilla and the Duchesses of Cambridge and Sussex, alongside all other royal women, will wear black dresses and black tights with a traditional hat and lace black veil in some form.
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Known as the 'mourning veil', the black lace veil signifies the wearer is grieving and also allows the person more privacy when they are wearing it.
As is custom, other funeral attendees will also wear black to the service - the historic colour for mourning.
The tradition was popularised by Queen Victoria, who wore black for 40 years following the passing of her husband, Prince Albert, in 1861.
While Kate and Meghan will be wearing black dresses and headpieces, one woman in the royal family may be dressed slightly differently.
The Queen's only daughter, Princess Anne, may be wearing her military uniform, as all working members of the royal family are required to at state occasions since the 19th century.
It is also expected that Camilla, Kate and Meghan will wear 'mourning jewellery' to Queen Elizabeth II's funeral, a tradition that also dates back to Queen Victoria.
She wore strands of pearls for the duration of her life, in a respectful nod to her late husband, as pearls are thought to represent tears.
Queen Elizabeth II honoured the tradition at Princess Diana, Princess Margaret and King George VI's funerals, and at Prince Philip's funeral last year, both the Queen and Kate were seen wearing pearl jewellery.
The Queen's funeral will begin around 9am on Monday and will include a procession through London which will allow well-wishers to say their final farewells to the late monarch.
There will be a minute's silence held around the country as the Queen's coffin enters Westminster Abbey.
The royal family, world leaders, politicians and the Queen's friends will attend the historic event.
Following the service, there will be a full military parade which will end at Hyde Park Corner, where the hearse will travel by road to Windsor Castle.
You can now buy Friday's historic Daily Mirror commemorating the death of the Queen here: mirror.co.uk/commemorative
