Royal watchers around the world were delighted to see the Princess of Wales join her family at Trooping the Colour this weekend, and Gwyneth Paltrow was clearly no exception.
The actress unexpectedly commented with a message of support for royal mother-of-three Kate on an official Instagram post.
"So happy to see you looking so happy and well," the Oscar winner wrote, adding a red heart emoji.
Princess Kate's return to public life
The royal family celebrated the King's birthday parade, known as Trooping the Colour, on Saturday, with the Princess of Wales making her first public appearance this year.
The crowds cheered and applauded as Kate, 42, who has been receiving treatment for an undisclosed form of cancer since late February, was joined by her three children, Prince George, Princess Charlotte and Prince Louis, in a carriage for the traditional procession.
Appearing in great spirits, Kate was surrounded by other members of the family, with her husband the Prince of Wales, Colonel of the Welsh Guards, on horseback, as were the Princess Royal, Colonel Blues and Royals, and the Duke of Edinburgh, Colonel Scots Guards.
When was Kate's last public appearance?
The royal mum-of-three was last seen publicly on Christmas Day when she and her family attended church in Sandringham.
As the royals made their way to St Mary Magdalene church, Kate held her daughter Princess Charlotte's hand.
The Waleses were seen chatting with locals in the crowd who had gathered to catch a glimpse of the royals on Christmas Day, with Kate accepting bouquets of flowers.
Earlier in December, extended members of the royal family also stepped out to attend Kate's Christmas carol concert at Westminster Abbey. Unfortunately, she wasn't able to return to work in the new year as expected.
Princess Kate's diagnosis
The Princess sent shockwaves around the world just before Easter when she shared the upsetting news that she had been diagnosed with cancer.
The Princess underwent major abdominal surgery in January, which was successful. At the time, it was thought that the condition was non-cancerous and no tests had confirmed the presence of cancer.
However, post-operative tests subsequently found that cancer had been present and the royal explained in a heartfelt video statement that she would be having "preventative chemotherapy."
At the time, Buckingham Palace released a statement which said: "His Majesty is ‘so proud of Catherine for her courage in speaking as she did. Following their time in hospital together, HM has remained in the closest contact with his beloved daughter-in-law throughout the past weeks.
"Both Their Majesties will continue to offer their love and support to the whole family through this difficult time."
Kate's updates
The Prince of Wales gave a positive update about his wife's treatment during a visit to the Isles of Scilly earlier in May, saying "she's doing well" when questioned by a hospital administrator.
At the end of May, Kensington Palace also shared an update on Kate's work amid her ongoing recovery, with the Princess expressing excitement over her Business Taskforce's report around prioritising early childhood.