Princesses Eugenie and Beatrice's children August and Sienna pictured together for first time in sweet photo

Princess Beatrice has yet to share any official photos of her daughter, Sienna, but her sister, Princess Eugenie has given fans a glimpse of the 18-month-old in an adorable picture alongside her cousin.

Eugenie took to Instagram on Saturday in honour of World Earth Day and posted a sweet photo of her son, August, standing next to Sienna during a family trip to London Zoo.

The image marks the first time August and Sienna have been seen together publicly and they already look like the best of friends.

Both children have their backs to the camera with their tiny hands pushed up against a glass enclosure as they admire some penguins.

Sienna's fiery red hair looks adorable, and she is wrapped up in a cream borg coat, pale chinos and black trainers. August, meanwhile, looked cool in dark denim jeans and a beige coat with a white shearling collar.

Alongside the image, Eugenie wrote in part: "It's World Earth Day and today is all about celebrating our planet and people doing amazing things that help protect it.

"Photo 1: August and his cousin Sienna love going to the London Zoo. It's part of the Zoological Society of London @zsllondonzoo a global wildlife conservation charity that helps to restore habitats and protect wildlife. Every time you visit you are supporting their work."

Eugenie's followers loved the rare snapshot, with one commenting: "How wonderful and cute." A second said: "So lovely to see. So cute."

It's no surprise that August and Sienna have become close considering the strong bond between their mums.

Beatrice shares her only child with her husband, Edoardo Mapelli Mozzi, whom she married during lockdown in 2020. Sienna Elizabeth Mapelli Mozzi was born on Saturday 18 September at the Chelsea and Westminster Hospital. She is currently tenth in line to the throne.

Beatrice and Edoardo shared a sweet artwork of their daughter's tiny footprints with the announcement. Shortly after the birth, a family friend of the couple explained the sweet meaning behind the name Sienna.

"They were looking for an Italian name which started with an S for Sarah, to honour the Duchess [Sarah Ferguson], and also reflected the golden rust colour of both the Duchess's hair colour and Beatrice's, which the new baby shares," they said.

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