Lady Elizabeth Shakerley was the Queen's cousin and a close personal friend of Her Majesty. She died at the age of 79 last November, and was well-known as an events planner, including one that was held before the wedding of the Duke and Duchess of Cambridge. Sophie and Sarah weren't the only royals at the event as Prince Michael of Kent and his daughter Gabriella Windsor were also in attendance.
WATCH: Sophie Wessex breaks down in tears as she remembers Prince Philip
Also paying their respects were Princess Beatrix of the Netherlands and Dame Joanna Lumley.
Sophie looked so elegant in a sleek green dress that she paired with a pair of black heels and matching hat.
Sarah looked splendid as she arrived at the service in a tan coat adorned with buttons and feathers, alongside a black skirt and tights.
Sophie wore an elegant green dress
When Lady Elizabeth married Sir Geoffrey Shakerley back in 1972, the Queen, alongside the Queen Mother were guests. Princess Anne served as a bridesmaid for the wedding held at Westminster Abbey.
The couple, who divorced in 2009, shared one child, Fiona, who was born in 1973. Fiona married Edward Brocas Burrows in 2004 and the couple share two children: Noah and Ruby.
Fiona, her husband and their children also attended the service, with Fiona looking striking in a pleated dress and blue tweed jacket.
Sarah had a beautiful outfit
Lady Elizabeth was born in Windsor Castle in 1941, the daughter of Thomas Anson, Viscount Anson, and his wife, the Queen's niece, Anne Bowes-Lyon.
Before her death, the Queen awarded her cousin a great honour, making her a Commander of the Royal Victorian Order on 31 March.
The Royal Victorian Order is a dynastic order of knighthood that was established in 1896 by Queen Victoria.
It recognises distinguished personal service to the monarch, members of the monarch's family, or to any viceroy or senior representative of the monarch.
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