To mark Father's Day - Kensington Palace released a couple of heart-warming pictures.

The first was a throwback snap of Charles with princes William and Harry. The next showed William hugging Prince George, his eldest of two children.

Happy Father's Day. Wishing all the fathers out there a very happy day pic.twitter.com/Lgm0ZnOCMT

— Kensington Palace (@KensingtonRoyal) June 18, 2017

"Happy Father's Day. Wishing all the fathers out there a very happy day," the accompanying caption read on Twitter. So far, so standard, you might think. Except it didn't take the internet long to ask one very important question: namely... just where is Charlotte? Charlotte, of course, is William and Catherine's adorable two-year-old daughter - a cute-as-a-button little sister to the almost four-year-old George. Some observers dug out snaps showing Wills with both his babies - presumably to show that such gorgeous snaps do indeed exist. Others responded with a mixture of bemusement and criticism at the decision to exclude the youngest little royal. "Hope for better pics next time to include both children," said one. Another used the hashtag #daddysgirl and asked simply: "Where is Princess Charlotte?" A third commentator opted for: "Odd there's only picture with his son? Where's his daughter?" We also reckon it's a pretty strange oversight by the British royals - but we're sure that William is today being spoilt rotten by his family regardless. Happy Father's Day!