Queen Mary and King Frederik's bittersweet balcony appearance

King Frederik and Queen Mary made a special appearance on the balcony of Frederik VIII's Palace in Amalienborg, Copenhagen, to mark the monarch's 58th birthday.

But Tuesday's appearance was bittersweet for the family as it came just a day after His Majesty's mum, Queen Margrethe II, was hospitalised again following her heart attack.

It was also a change for the Danish and Australian couple, with only two of their four children joining them for the occasion.

Twins Prince Vincent and Princess Josephine, 15, who recently marked their confirmation, celebrated their dad's birthday with waves to the massive crowds outside the palace.

Older siblings Crown Prince Christian, 20, and Princess Isabella, 19, weren't in attendance.

It's understood this is because the King's birthday isn't a public holiday in Denmark and Prince Christian is currently in intensive military training, while Princess Isabelle is weeks out from graduating high school.

King Frederik wore a blue pinstripe suit with a pink tie for his birthday appearance and sported a beard.

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Queen Mary donned a chic grey rosette blouse with white trousers and coral drop earrings.

A new portrait of the King in uniform in the Throne Hall at Christiansborg Castle was released by the Danish Royal Household on social media to celebrate his birthday.

The palace also shared a video of the festivities on social media, showing loads of people filling the grounds of Amalienborg, with a few Aussie flags among the Danish ones.

Australian-born Mary became Queen 20 years after marrying into the one of the world's oldest monarchies, after meeting then-Crown Prince Frederik during the Sydney Olympics.

But the Tasmanian beauty has been warmly accepted into the hearts of Danes, who are happy to fly the Australian flag at such occasions in honour of their Queen.

Queen Margrethe stepped down from the throne in January 2024, after a 52-year reign, following a number of health battles the prior year and undergoing major back surgery.

The 86-year-old suffered a heart attack earlier this month and spent five days in hospital before being discharged, to continue her recovery at home.

However, on Monday the monarch was readmitted to Rigshospitalet after a large blood clot was found on her hip, a result of her fall last September.

She'll remain in hospital for a number of days, the Danish Royal Household said.