As Buckingham Palace announces the good news that King Charles will return to public duties as his medics are 'positive' about his progress, he has thankfully been able to count on close and loyal family members while he undergoes treatment - including Princess Anne.

The Princess Royal, 73, has long been dubbed the hardest-working royal - a title well-earned by the mother-of-two, who carried out 457 engagements in 2023, the most undertaken by any royal that year.

While Anne has long had a reputation for her dedication to duty, it has perhaps been highlighted more so than ever since the King revealed his shock cancer diagnosis in January - at the same time the Princess of Wales has also been having chemotherapy.

With both Charles and Kate out of action while they undergo treatment, and Prince William taking time out to look after his wife while she has preventative chemotherapy, many royal fans worried there may be a hole at the heart of the King's 'slimmed-down monarchy - but, as ever, the royals were able to count on Princess Anne.

While King Charles is set to make a gradual return to public engagements following his cancer diagnosis, Princess Anne has  continued to hold the fort (Anne is pictured in March)

His Majesty is not yet clear of cancer and is still undergoing treatment, but his medical team are understood to be 'pleased with the progress made so far' and 'remain positive' about his recovery. 

While Camilla has been by King Charles's side throughout his treatment and been the face of the monarchy, Princess Anne has quietly continued with business as usual as she carries out visits and hands out investitures.

In a statement tonight, Buckingham Palace said: 'His Majesty The King will shortly return to public-facing duties after a period of treatment and recuperation following his recent cancer diagnosis.

'To help mark this milestone, The King and Queen will make a joint visit to a cancer treatment centre next Tuesday, where they will meet medical specialists and patients. This visit will be the first in a number of external engagements His Majesty will undertake in the weeks ahead.

'In addition, The King and Queen will host Their Majesties The Emperor and Empress of Japan for a State Visit in June, at the request of HM Government.

'As the first anniversary of The Coronation approaches, Their Majesties remain deeply grateful for the many kindnesses and good wishes they have received from around the world throughout the joys and challenges of the past year.'

The King's diagnosis first became public in January when it was announced that he was going into hospital for surgery on an enlarged prostate. He remained in The London Clinic for three days.

The 73-year-old royal continued to carry out investitures during the difficult period, including to Daily Mail columnist, Jefferey Powell (pictured)

The Princess Royal has been dubbed the King's 'right-had woman' is recent times (pictured in 2023) 

The Princess Royal during a visit to the Off The Streets knife crime community group, in Wellingborough, Northamptonshire 

At the time it thought that the condition was not cancerous, but in February it was revealed subsequent tests had discovered presence of the disease elsewhere in his body.

Just 24 hours later, it was Princess Anne who took the lead in putting on a brave face as she handed out honours, including MBEs. 

Among those receiving honours from the princess was Sara Cox, the world's first professional female rugby referee, who was made an MBE for her services to rugby union.

She earned her first contract with the Rugby Football Union in 2016 and has since gone on to achieve a number of firsts in the sport, including officiating a match between two men's Premiership Rugby teams.

That afternoon, the Princess visited a community centre in Eastwood, Nottinghamshire, where she learned about a new project helping local people with their mental health. 

Elsewhere in February, Anne was photographed undertaking one of her many engagements today as she visited an organisation in Northamptonshire.

Anne teamed up with Sophie, Duchess of Edinburgh, in March to host a reception for Korean war veterans

The pair proved they were quite the power duo as they stepped in King Charles 

The 73-year-old royal was shown a knife amnesty bin as she visited a group that works to combat stabbings in Wellingborough, called Off The Streets knife crime community group.

During the engagement, King Charles' sister met volunteers from Off the Streets North Northamptonshire (NN) and heard from those affected by knife crime during the visit at the market town's Hind Hotel.

Off the Streets NN co-founder Ravaun Jones gave Anne a demonstration of a bleed control kit and a knife amnesty bin.

Anne presented certificates to individuals who had supported the organisation and listened to two local schoolchildren read out pieces they had written on knife crime.

In March, Anne kept her schedule jam-packed - holding meetings for two charities at Gatcombe Park, her country home in Gloucestershire, visiting a young offender's institute in Buckinghamshire, and opening a sheltered housing scheme, to name a few. 

The Princess Royal alongside Lord Lieutenant of Dumfries Fiona Armstrong before laying a wreath at the Lockerbie Air Disaster Memorial in March

Anne appeared in high spirts after attending the Easter Matins Service at St. George's Chapel alongside Vice Admiral Timothy Laurence (C)

On the same day she attended an event to mark the 180th anniversary of New Court Place, a residential home for disabled people run by the charity Livability, which Anne is patron of.

The Princess Royal and Duchess of Edinburgh proved they make quite the power duo at the end of March as they hosted a reception for Korean War Veterans together.

Stepping in for King Charles III, Anne and Sophie, 59, appeared in high spirits as they chatted with attendees at Buckingham Palace, central London.

The pair showed their ongoing support for Charles and dutifully carried out the engagement, greeting various veterans at the intimate event, which set out to mark the 70th anniversary of the end of the Korean War.

Anne made Paul Hollywood, baker and television presenter, a Member of the Order of the British Empire earlier this month 

The 73-year-old has maintained a jam-packed schedule following the King's shock cancer diagnosis (seen in February)

Anne has supported her brother throughout the difficult time with hardworking approach to royal engagements (seen in June 2022)

Anne also travelled to the Lockerbie air disaster memorial site at the end of March, meeting  representatives from Police Scotland, Dumfries and Galloway Council, and Dryfesdale Lodge Trust.

Pan Am Flight 103 exploded over the town in Dumfries and Galloway, 40 minutes into its flight from London to New York, killing all 259 passengers and crew on board, along with 11 Lockerbie residents.

The Princess royal continued to put on a brave display at the start of this month during the annual Easter service. 

King Charles' three younger siblings joined the monarch at St George's Chapel in the grounds of Windsor Castle for the church service on 1 April.

It marked the King's first major public royal engagement since his shock cancer diagnosis was announced in February.

Speaking to FEMAIL, body language expert Judi James said Princess Anne, 73, demonstrated her 'protectiveness' towards her brother from the outset.

The expert noted: 'The royal body language message here is clearly one of resilience, unity and upbeat strength.'

Analysing Anne's body language on arrival Judi said: 'Anne and husband Tim set the mood-music as they stepped out of their car.

'The couple rarely indulge in an chatting or joking in public but this time they did. Anne grinned at Tim as she emerged and he even turned to smile at the fans.

'Anne's wave and her warm, connecting smile at the crowd seemed to signal thankfulness and even some reassuring relief.'