William and Kate admit facing 'difficult time' since Prince Philip's death

In a tribute to the royal upon his death on April 9, Kate and William had shared a number of never-before-seen pictures of him with their children.

Prince William and Kate Middleton have opened up about the difficult times the British royal family has been facing since the death of Prince Philip in April this year.

Gert's Royal Replies, which routinely shares the replies the British royals make to their fans, recently revealed the contents of a note the Duke and the Duchess of Cambridge sent in response to a condolence message following Prince Philip's demise.

The reply was sent in an envelope adorned with a royal mail stamp from the Court Post Office at Buckingham Palace and William and Kate's individual monograms. The backside of the envelope featured the Kensington Palace black coronet logo.

The envelope contained a folded card, the front of which featured the couple's individual monograms, W & C under the coronets of the Children of the Heir Apparent. The back had a photo credit, (c) Anthony Devlin, for the picture inside.

Inside the card, there is a photo of Prince Philip in his military dress from 2012 from the day he attended the Queen's Diamond Jubilee Armed Forces Parade and Muster at Windsor Castle on one side. The other side contained a typed note, with both pages outlined with a black border that represents mourning.

The message in the card read, "The Duke and Duchess of Cambridge thank you for your kind words following the death of The Duke of Edinburgh. Their Royal Highnesses have been incredibly moved by the many thoughtful messages they have received in recent weeks."

"They will all miss their much loved grandfather and great-grandfather, but your message has provided great comfort at this difficult time," the note further read.

In a tribute to the late Prince Consort upon his death on April 9, Kate and William had shared a number of never-before-seen pictures of him with their three children- Prince George, eight, Princess Charlotte, six, and Prince Louis, three. In a message shared on Kensington Palace's social media accounts, William said about the late royal, "I will always be grateful that my wife had so many years to get to know my grandfather and for the kindness he showed her. I will never take for granted the special memories my children will always have of their great-grandpa coming to collect them in his carriage and seeing for themselves his infectious sense of adventure as well as his mischievous sense of humour!"