Kate Middleton is letting her admirers know that their birthday wishes were appreciated! As People reports, Kensington Palace has mailed out a token of thanks to those who wished Kate a happy 38th birthday in January. The envelope stamped with "Royal Mail" includes a thank you letter, as well as a photo card featuring the portrait of her released on her special day.

The letter features the Kensington Palace logo, and is written on behalf of Kate. "The Duchess of Cambridge thanks you for taking the trouble to write on the occasion of her 38th Birthday," it reads. "Your thoughtfulness was greatly appreciated by Her Royal Highness who sends her warmest thanks and best wishes".

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Kate's birthday photo card from 2018 family photo session

Kate's birthday photo itself may be new, but the photo session it's from took place back in 2018! Wearing a sweater and jeans, Kate looks relaxed and casual as she sits on a fence while smiling for the camera. The Duke and Duchess of Cambridge first shared a photo from the session the same year, when it was revealed to be their 2018 Christmas card photo... their first as a family of five!

And just this past March, another photo from the session was shared on the Kensington Royal Instagram in honour of Mother's Day in the United Kingdom. This time, Kate is featured with daughter Princess Charlotte on her back! 

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See the photo card and thank you letter sent out by Kensington Palace on behalf of Kate Middleton here!

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