The Queen attended two of her great-grandchildren's royal christenings on Sunday, and there was a poignant significance behind the date chosen.
When both babies were born earlier this year, Princess Eugenie and Zara gave their sons the middle name Philip in a touching tribute to their grandfather, the Duke of Edinburgh. Prince Philip passed away aged 99 on 9 April when August was just two months old, and Lucas was less than three weeks old.
WATCH: British royal christenings through the years
The royal cousins' joint christening took place on 21 November – one day after what would have been the Queen and Prince Philip's 74th wedding anniversary.
In what would have been a difficult weekend for the monarch, no doubt she would have taken comfort by being surrounded by her closest family members.
The Queen was pictured leaving her great-grandsons' christenings
The royal double christening also took place 181 years after the birth of Queen Victoria and Prince Albert's eldest child, Victoria, Princess Royal, who was born on 21 November 1840. The original Spitalfields silk and Honiton lace christening gown was worn by Victoria at her christening in February 1841 and it was worn by 62 royal babies, including the current Queen.
Princess Eugenie's son August was born in February
However, following the baptism of the Earl and Countess of Wessex's daughter, Lady Louise Windsor, on 24 April 2004, it was decided the garment was too delicate to be used again, so the Queen commissioned an exact replica to replace the original robe.
The replica gown has since been worn by the Duke and Duchess of Cambridge's three children, Prince George, Princess Charlotte and Prince Louis, along with the Duke and Duchess of Sussex's eldest child, Archie.
It is now known whether Princess Eugenie and Zara's sons took it in turns to wear the gown for their baptisms, but a double royal christening is very rare.
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