With Prince Philip, 99, spending his third night in hospital after being admitted on Tuesday, Prince Harry, 36, is reportedly self-isolating at home with pregnant wife Meghan Markle, 39, and their son Archie in case he needs to return to the UK with short notice.
The Duke of Sussex has reportedly organised a private jet to fly to Britain if necessary, according to The Mirror.
"Harry is of course concerned for his grandfather’s welfare and is being kept regularly informed on his condition," a source told the publication.
"He has chosen to stay in case he is required to return to the UK at short notice."
It's believed Harry will be tested for coronavirus before leaving the US and upon his arrival in the UK. The US could soon be added to the "red list" of countries which will mean passengers will need to quarantine in the Government's organised hotels.
It's unknown whether Meghan will travel to the UK as she is five months pregnant.
Philip was reportedly in "good spirits" after being admitted to the private King Edward VII's hospital in central London, according to The Daily Express.
While the reason for the Duke of Edinburgh's hospital visit has not been disclosed, it is not coronavirus-related.
The Duke was reportedly taken to hospital by car and walked inside without help as a non-emergency admission.
Buckingham Palace said in a statement on Wednesday: "His Royal Highness the Duke of Edinburgh was admitted to King Edward VII's Hospital in London on Tuesday evening.
"The Duke's admission is a precautionary measure, on the advice of His Royal Highness's doctor, after feeling unwell.
"The Duke is expected to remain in hospital for a few days of observation and rest."
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