Kate's behind-the-scenes snaps from George and Charlotte's photoshoot with the Queen

By Ainhoa Barcelona

The Duchess of Cambridge couldn't let the opportunity slip by to take some personal photos of her own when her children Prince George and Princess Charlotte posed for official portraits withthe Queen. The Duchess took her children to Windsor Castle on Easter Monday for a photoshoot with Her Majesty to celebrate the royal's upcoming 90th birthday.

The official photographer at the shoot was Annie Leibovitz, whose famous subjects include Kate Moss, Johnny Depp, Lady Gaga and the Kardashian-Wests.

But Kate, who is a keen shutterbug, captured her own personal snaps for the family album.

TAP TO VIEW GALLERYgeorge-queen-- "The Queen loves her great-grandchildren and is very proud of them," a royal source said

" Wills and Kate were with the children but as adoring parents rather than wanting to be in the pics themselves," a royal source told The Sun.

"Annie was taking the official pictures but Kate took her own snaps for the family album. It was really cute.

"The Queen loves her great-grandchildren and is very proud of them. The pictures will be a lovely way to mark a remarkable 90th birthday."

Cambridge family portrait Kate took pictures of George and Charlotte with the Queen during an official photoshoot

The report comes shortly after a documentary about Her Majesty, Our Queen at Ninety, aired on ITV on Easter Sunday. Kate revealed that the monarch always leaves out gifts for Prince George and Princess Charlotte when they go to stay with her, adding that George calls his great-grandmother "Gan-Gan".

"She always leaves a little gift or something in their room when we go and stay and that just shows her love for her family," said Kate.

close up of the Duchess of Cambridge and Queen Elizabeth II Kate revealed that she gave the Queen some homemade chutney for Christmas

She added: "I can remember being at Sandringham for the first time at Christmas and I was worried what to give the Queen as her Christmas present. And I was thinking, 'Gosh! What shall I give her?'

"And I thought back to perhaps what would I give my own grandparents. I thought I'll make her something, which could have gone horribly wrong. I decided to make some – actually it was my granny's recipe for chutney. And I was slightly worried about it.

"But I noticed the next day that it was on the table. And I think such a simple gesture went such a long way for me. I've noticed since that she's done that on lots of occasions and I think it just shows her thoughtfulness really – her care in looking after everybody."

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