The Queen turned 95 on Wednesday, her first birthday since the death of her husband, Prince Philip on April 9.
Her Majesty spent the day privately with family members at Windsor Castle, but her granddaughter-in-law, Kate Middleton, made sure to pay a sweet birthday tribute while out on an official engagement.
Kate, 39, was joined by Prince William to pay a visit to the 282 East Ham Squadron Air Training Corps in London.
Both were dressed in black out of respect for the late Duke of Edinburgh, with the duchess sporting a smart Dolce & Gabbana military-inspired coat with gold buttons.
In a subtle tribute to the Queen, the mother-of-three also wore a pair of simple yet elegant diamond and pearl earrings which Her Majesty first donned for her 1977 silver jubilee.
It's not the first time Kate has borrowed the 'silver jubilee earrings,' having worn the meaningful pieces in 2016 during her first solo trip to the Netherlands.
Shop Kate's look
While Her Majesty's silver jubilee earrings are no doubt rather pricey, we've found a few similar pieces that are slightly easier on the wallet but with a bit of royal flair.
Honouring the duke
The Cambridge's visit to the air training corps was in itself a tribute to Prince Philip, who was the Honorary Air Commodore-in-Chief of the Air Training Corps for 63 years.
Prince Philip passed the role to Kate in 2015, who is now honorary Air Commandant of the Air Training Corps.
William and Kate watched as cadets gave three cheers for the late duke at the end of the visit, having seen them take part in field craft exercises and leadership tasks.
Kate also tried out a flight simulator, with William, 38, saying "I’ll hold the handbag" while she gave it a go.
She was talked through the controls of the Grob tutor, a light aircraft that thousands of cadets use each year for air experience flights.
As she was given a headset with a paper covering over the microphone, William said: "Flight safety in an age of COVID."
William was a helicopter pilot for several years, in the RAF and then for East Anglia Air Ambulance. He still maintains his flying hours — as his grandfather did.
The couple was left giggling at one moment as they observed a demonstration of a problem-solving exercise.
They watched cadets move items including a fire extinguisher and a teddy bear with ropes and William laughed as he said: "Whose teddy bear is that?"
William has previously said his grandfather would have wanted them to get on with the job, in a tribute to Philip, indicating they would not spend too long behind closed doors in mourning.
Princess Anne has also been carrying out engagements, visiting the Isle of Wight before her father's funeral, and attending online visits since then.
And on Wednesday she went to three hospitals in Gloucester where she opened a commemorative garden, and thanked staff for their work during the last 13 months.
'Period of great sadness'
On her birthday, the Queen released a sombre statement thanking people for their tributes and well wishes after the death of Prince Philip.
In a personal statement, she said: "I have, on the occasion of my 95th birthday today, received many messages of good wishes, which I very much appreciate.
"While as a family we are in a period of great sadness, it has been a comfort to us all to see and to hear the tributes paid to my husband, from those within the United Kingdom, the Commonwealth and around the world.
"My family and I would like to thank you all for the support and kindness shown to us in recent days. We have been deeply touched, and continue to be reminded that Philip had such an extraordinary impact on countless people throughout his life."
Additional reporting by Rebecca C Taylor.
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