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Mom and daughter - In this image, Kate Middleton seems to be chastising Charlotte for having her tongue out. But we can't be sure, considering that earlier the duchess was herself joining in on the fun antics.

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Archie's christening - Prince Harry and Meghan Markle's son, Archie Harrison Mountbatten-Windsor, was christened on July 6 at an intimate service in the Private Chapel at Windsor Castle.

© Chris Allerton ©️SussexRoyal

Little Archie - Archie was baptized wearing a handmade replica of the traditional royal christening gown.

© Chris Allerton ©️SussexRoyal

Prince Harry and Meghan Markle - Prince Harry and Meghan Markle revealed their newborn baby to the world on May 8, two days after he was born.

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The youngest royal - Here's a close-up of the newest member of the British royal family!

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Princess Charlotte - Now, let's get acquainted with Archie's royal cousins, starting with Princess Charlotte.

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Princess Charlotte - The princess was born at St Mary's Hospital in London in 2015.

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Princess Charlotte - Charlotte is fourth in line to the throne, and is officially titled Her Royal Highness Princess Charlotte of Cambridge.

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Prince Louis - Prince Louis poses at Sandringham House in Norfolk, England.

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Prince Louis - Louis smiles at the sky during a photoshoot at Sandringham.

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Prince Louis - Louis looks pretty happy while exploring his natural surroundings.

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Prince Louis' christening -

The family leaves the Chapel Royal at St James's Palace in London after Prince Louis' christening in 2018.

© Reuters 

Tongues out! -

Princess Charlotte sticks out her tongue (no surprise now!) while on the way to Prince Harry and Meghan Markle's wedding.

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Suited up -

Prince George steps out for Harry and Markle's fairytale wedding.

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Wedding outfits -

The boys and girls match in these gorgeous white and black outfits, again at Harry and Meghan's wedding.

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Meeting their sibling -

George and Charlotte on the way to see newborn Prince Louis at St Mary's Hospital in London.

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Meeting their sibling - Any minute now!

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Prince Louis - Prince Louis shows his face to the world.

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Prince Louis - Prince Louis held by his mother.

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Teary eyed -

Princess Charlotte looks teary eyed before boarding a plane in Germany.

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Walking the runway - The royal family walk along an airfield in Germany.

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Shy -

Prince George looks pretty shy during an appearance in Berlin.

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Dressed up for auntie's wedding -

Charlotte and George wear matching outfits at the wedding of Pippa Middleton and James Matthews in 2017.

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Christmas outfits -

The family get ready for the Christmas Day service at St Mark's Church in Englefield, England.

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Boarding for departure -

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Furry friend - Princess Charlotte meets a rabbit at Government House in Victoria, Canada.

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Ready to party -

The awesome foursome join a children's party in Victoria, Canada.

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Ballooning - Charlotte plays around with balloons at the children's party.

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Bubble -

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More furry friends -

Princess Charlotte pets another furry friend at the children's party.

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Back on the runway -

Prince George holds his mom's hand at Victoria Airport in Canada.

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Running away - George runs away from his dad at RAF Fairford in Gloucestershire, England.

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Not plane-ing around -

William lifts George out of a Red Arrows plane at RAF Fairford.

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Is it a bird? -

It's eyes to the sky at the annual Trooping the Colour ceremony in 2016.

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George and Charlotte -

Prince George looks at his sister, Charlotte, in her pram at Sandringham in 2015.

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George and Charlotte -

George and Charlotte have never looked cuter. 

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Waving to the cameras - William and George go to see newborn Charlotte in 2015.

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Exploring the museum -

George explores the Natural History Museum with his parents.

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Feeling grumpy -

George looks a little grumpy before boarding a plane to Canada.

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Playing around -

Prince George plays around at Sydney's Taronga Zoo in 2014.

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Hair raiser -

Prince George touches his mom's hair at Government House in Wellington, New Zealand.

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Christening -

Prince George doesn't know what to think after his christening at St James's Palace in 2013.

See also: The best looks from the British royal family.

© Reuters