Princess Charlotte looks just like *this* relative in new throwback picture

And no, it's not the Queen!

Princess Charlotte Lady KItty Spencer

Princess Charlotte has been compared to this royal many times before, but this new picture cements her as Charlotte's number one lookalike.

Lady Kitty Spencer shared an adorable childhood throwback picture to celebrate her 29th birthday - and royal fans were quick to notice how similar she looks to her young relative, Princess Charlotte.

"Kitty is Charlotte!" one fan commented. While another follower wrote, "I thought it was Princess Charlotte."

"She resembles Princess Charlotte," noticed a third.

A photo posted by on

The post, which has already amassed over 13K likes was captioned, '29 🎂 Thank you for such beautiful and kind birthday messages today 💗💗 I couldn’t have asked for a better day surrounded by the people I love ☀️🙏🏽 Thank you to everybody who made it the most special birthday I can remember (although this Barbie party looked pretty cool too!) 💗'

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People were quick to comment on the post wishing Lady Kitty Spencer a happy birthday, too.

'Happy happy bday Kitty ❤️ wishing you all the best ✨' wrote one. While another said, 'World is a more beautiful place with you@kitty.spencer💫 muse forever 🌷'.

Charlotte has also been compared to Queen Elizabeth II on numerous occasions. Looking at this old picture of the Queen as a child, it's easy to see the resemblance!

Princess Charlotte Lady Kitty Spencer

The young royal, who is the middle child of the Cambridges, is growing up fast. Catherine has previously revealed how Charlotte is already taking an interest in hobbies like photography.

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Speaking at aphotography workshop to mark her newest patronage with The Royal Photographic Society earlier this year, the royal gave some tips on how to get the perfect photograph. She said, “Just look at everything around you. Maybe it’s in front of you, or far away but choose your subject and focus on it.

“Get outside with your camera as well. George and Charlotte love it when we do that."