Resilient Prince Philip's appears to be facing his toughest health battle yet after experiencing his longest hospital stay to date.
The Duke of Edinburgh, 99, was admitted to King Edward VII's Hospital in London on Tuesday, February 16 as a precautionary measure after feeling unwell.
Today, he was transferred to St Bartholomew’s Hospital where his treatment for a pre-existing heart condition and an infection will continue.
The hospital is described on the Barts Health NHS Trust website as an "internationally-renowned" hospital which is a "centre of excellence for both cardiac and cancer care".
A palace spokesman said the Duke "remains comfortable and is responding to treatment".
While the pre-existing heart condition has not been mentioned extensively in reports on the Duke's health - he has suffered with chest pains and undergone procedures as a result in the past.
The Duke's hospital visits in his younger days were largely as a result of polo or sporting accidents and in 1961, he suffered a broken bone in his ankle on the polo field, before suffering a pulled ligament in 1964 after falling off his horse.
In 1987, Prince Philip was hospitalised for a hernia repair, while a small benign growth was removed from his nose in 1996.
In 2008, when the Duke was aged 87, the palace spoke out about his health to deny reports he had been diagnosed with prostate cancer - while the following January saw him miss a string of events due to a pulled back muscle while carriage driving - testament to his good health.
The Duke's health did take a more serious turn when he was rushed to hospital in late 2011, aged 90, suffering from chest pains before being treated for a blocked coronary artery.
While hardy Prince Philip underwent surgery to fit a coronary stent, missing the traditional Royal Family Christmas day service at Sandringham, once again he soon returned to the public eye.
Prince Philip's determination to carry out his royal duties remained unwavering, as he continued alongside the Queen at public events throughout the UK and across the world for a number of years.
In 2018, he was admitted to King Edward VII Hospital for planned surgery on his hip - with the palace confirming post-operation he was comfortable and in "good spirits".
Prince Philip attended hospital as a precautionary measure in January 2019 after he was involved in a car accident with a fellow motorist near the Sandringham estate.
Then 97, Philip had been driving his Land Rover that overturned after pulling from a driveway on the A149.
After being hospitalised two weeks ago, the Duke's current stay marks his longest yet - while the Queen and other royals have continued with their duties while the duke has been in hospital, although some have paid a visit.
Prince Charles, 72, paid the duke a 30-minute visit last weekend.
Charles, seen to be teary eyed during the visit - was the first member of the royal family to visit Philip.
He arrived at the hospital at around 3.20pm last Saturday in a grey Tesla car, and exited the vehicle wearing a face mask, before leaving around 30 minutes later.
His brother Prince Edward, 56, later told Sky News on Tuesday that his father was getting better.
The Earl of Wessex said: "As far as I'm aware, he's a lot better ... so he's looking forward to getting out which is the most positive thing.
Edward added with a laugh that his father was "just a bit" frustrated at being in hospital.
It has also emerged that Prince Harry is making plans to hastily return to the UK should his grandfather's condition worsen and is being kept "regularly informed" of developments.
The Duke of Sussex has already made arrangements to fly over from the US by private jet and is understood to be self-isolating at home with Meghan and Archie to ensure he can travel straight away.
