Amid the backlash, a royal expert has suggested Harry would have been beside himself with worry over his sibling’s safety, as he battled his secret illness across the pond.
Speaking to The Daily Star, Royal Central deputy editor Brittani Barger said it’s likely Harry was made aware of his brother’s condition but sworn to keep it under wraps.
She said despite reports of a worsening feud between the brothers, Harry would probably have kept in contact with Wills, as he remained under quarantine in the UK.
"I would think that Harry checked in on his brother when he found out that he had COVID. No matter what, that's his brother, and he wouldn't want him to have the virus,” Brittani said.
"I’m sure he was worried about him having it and Kate and the kids catching it. I think that is only natural,” she added.
The royal expert said the situation would have been extremely stressful for Harry, being as though he was located half way across the world in Los Angeles.
"I would think Harry was told personally about William having COVID. I don't think that would be something they'd let him find out with the rest of the world. They are family, so I'm sure he was told by someone in the family,” she added.
What’s more, it has been suggested that, at one point, the Duke of Cambridge suffered from breathing difficulties – and if that's the case, the news would have undoubtedly been stressful for Harry.
"At one stage [Prince William] was struggling to breathe, so obviously everyone around him was pretty panicked," a source sensationally claimed to The Sun.
Despite the claim, the source went on to allege that, after receiving treatment for his hidden illness, William was able to successfully carry out his duties from his Norfolk home.
"After seeing medics and testing positive - which was obviously quite a shock given how fit and healthy he is - William was determined it should be business as usual though," the source alleged.