Two royal babies were christened together on Sunday 21 November, in a huge first for the royal family.
MORE: The Queen attends Princess Eugenie and Zara Tindall's sons' christening
The son of Princess Eugenie and Jack Brooksbank, August, nine months, and the son of Zara and Mike Tindall, Lucas, eight months, were baptised in the presence of the Queen at the Royal Chapel of All Saints in Windsor.
WATCH: A look at British royal christenings
But many royal fans have been left wondering why Eugenie's sister, Beatrice, chose not to christen her baby girl, Sienna, at the same time – given the royal gathering.
Princess Eugenie was photographed on her way to the event
One likely reason could be Sienna's age. At just two months, she's very young and her royal parents may not have felt she or they are ready for such a big event. Royal babies are normally christened at around three or four months old, such as the Duke and Duchess of Cambridge's children, Prince George and Prince Louis, so Beatrice may be waiting just a little bit longer.
It also could be that Eugenie and Beatrice have followed in the footsteps of their mother, Sarah Ferguson, by choosing to wait a little longer to christen their children.
According to People, the former Duchess of York waited for Prince Andrew to return from his work as a naval flight commander, before they baptised a nine-month-old Princess Eugenie, while Princess Beatrice was four months at her christening.
LOOK:17 beautiful royal christening moments in photos
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Princess Beatrice on her own christening day
The royal sisters do seem to be taking after Sarah when it comes to their babies.
Back in 1988, the Duke and Duchess of York took two weeks to confirm Princess Beatrice's name. Both Eugenie and Beatrice also waited two weeks before revealing their babies' names to the public.
Another theory for Beatrice delaying Sienna's christening could also be to do with COVID-19 restrictions. Unlike her sister Eugenie, Beatrice had to have a small, private wedding ceremony due to pandemic rules.
The Princess and her husband Edoardo Mapelli Mozzi wed in a socially distanced ceremony at The Royal Chapel of All Saints at Royal Lodge, Windsor, on Friday 17 July 2020. They had originally planned a larger wedding for May that year but sadly had to rearrange.
Now restrictions are lifted, we wonder if Beatrice is hoping for a larger christening for Sienna, with photos of her daughter possibly released for the public to see.
Sienna would be able to wear the royal Honiton lace christening gown, which was made for Queen Victoria's daughter in 1841. The Queen, Prince Charles, Prince William and many more royals were all christened wearing the special family heirloom.
However, following the baptism of Lady Louise Windsor in 2004, it was decided the ancient garment was too delicate to be used again. As a result, the Queen commissioned an exact replica of the 1841 christening gown to replace the original robe. The new gown has since been worn by the Duke and Duchess of Cambridge's three children, Archie Harrison and James, Viscount Severn.
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