Princess Charlotte is often referred to as looking like her great-grandmother the Queen.
But royal fans have now pointed out her uncanny resemblance to a relative on the other side of her family - Lady Kitty Spencer.
Kitty is the niece of Princess Diana, Charlotte's late grandmother, making her a cousin of Prince William.
She has an active Instagram account, boasting over 755,000 followers and often posts images of her glamorous lifestyle.
In 2019, she posted a throwback picture of herself sitting on a horse as a young girl with the caption: "Lexus Melbourne Cup here we come!! Channelling my inner jockey since 1992!"
And in recent weeks, it has been unearthed by royal fans, who say they can't believe how much Kitty and Charlotte look alike.
One person wrote in the comments: "OMG! They look exactly alike! Adorable."
Another said: "Yup the Spencer genes are so strong."
While another admitted: "I thought it was Princess Charlotte."
Kitty, who is the daughter of Diana's younger brother Earl Spencer is the most well-known of the current crop of Spencers.
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The 30-year-old hit the headlines in July when she married wealthy businessman Michael Lewis, 62, in a stunning three-day wedding in Italy.
She wore a series of gowns by Dolce & Gabbana with her main dress, which had an intricate floral lace design, a high neck, long sleeves and puffed shoulders, reportedly taking six months to create.
The couple exchanged their vows in front of celebrity guests that included singer Pixie Lott, and Idris Elba's wife Sabrina at the Villa Aldobrandini in Rome.
Kitty grew up in South Africa with her mother Victoria, read psychology at the University of Cape Town and has modelled for brands including Dolce & Gabbana and Bvlgari.
She also scored invites to the wedding of her cousins William and Harry and her Instagram account shows her at fashion shows in cities such as London and Milan.
Although the monarchy has now changed to put sons and daughters on an equal footing in terms of ascending to the throne, British primogeniture law has not been changed to peers such as dukes and earls.
So her father Earl Spencer's title will go to his eldest son Louis rather than Lady Kitty or her sisters Amelia and Eliza, despite them being older.
