The Duke of Edinburgh is into his ninth day in hospital where he is being treated for an infection.
Buckingham Palace shared an update on the Duke of Edinburgh's health on Tuesday, saying: "The Duke of Edinburgh remains at King Edward's Hospital, where he is receiving medical attention for an infection. He is comfortable and responding to treatment but is not expected to leave hospital for several days."
The Duke, 99, was admitted on 16 February as a "precautionary measure" after feeling unwell.
WATCH: Buckingham Palace shares health update on Prince Philip
In an interview with Sky News on Tuesday, the Queen and Prince Philip's youngest son, the Earl of Wessex, said: "He's a lot better, thank you very much indeed, and he's looking forward to getting out, which is the most positive thing, so we keep our fingers crossed."
Asked whether Philip was frustrated to be in hospital, Edward laughed and replied: "Just a bit. I think that gets to all of us, and then you can only watch the clock so many times and the walls are only so interesting.
"We've had some brilliant and lovely messages from all sorts of people and we really appreciate that and so does he, I've been passing them on. It's fantastic, thank you."
Edward pictured with Philip in 2017
Prince William, 38, was asked how his grandfather is by royal photographer Arthur Edwards, to which the Duke replied with a wink: "Yes, he's ok, they're keeping an eye on him."
Charles visited his father in hospital on Saturday
The Duke of Edinburgh, who will mark his 100th birthday on 10 June, retired from public duties in 2017.
He and the Queen have been spending lockdown at Windsor Castle, although prior to the coronavirus outbreak, Prince Philip had resided mostly at Wood Farm on the Sandringham estate in Norfolk during his retirement.
The couple share four children, eight grandchildren and will welcome their tenth and 11th great-grandchildren when the Duchess of Sussex welcomes her second child and when Zara Tindall gives birth to her third this year.
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