Members of the British royal family, such as Prince Charles, William, and Harry, are expected to always show up for previously arranged public appearances. For this reason, it’s not too surprising for fans to be concerned with Camilla, Duchess of Cornwall, after she failed to attend a very important event on Friday for health issues.

Camilla was a no-show at the Westminster Abbey’s Field of Remembrance opening ceremony leaving only Prince Harry and Meghan Markle to represent the royal family in the important event. But, the Duchess of Cornwall as a very valid excuse for not attending – her absence was upon doctor’s orders due to chest infection.

“The Duchess of Cornwall has been told by her doctor to cancel her engagements owing to a chest infection which has got progressively worse over the last few days,” a statement from Clarence House reads.

But, some outlets are now reporting that Camilla’s health issue can be a serious concern. According to Express, concerns about the duchess’ health are justified because chest infections are “potentially ‘life-threatening.”

The publication’s claim is, actually, backed by the UK’s National Health Service (NHS). “A chest infection is an infection of the lungs or large airways. Some chest infections are mild and clear up on their own, but others can be severe and life-threatening,” NHS’ chest infections guidelines read, as quoted by Express.

NHS also listed some symptoms of chest infections that include headache, fever, tiredness, chesty cough and shortness of breath. In severe cases, the infection may even last for weeks.

“These symptoms can be unpleasant, but they usually get better on their own in about 7 to 10 days,” NHS continued. “The cough and mucus can last up to 3 weeks.”

Patients suffering from chest infections are advised to get plenty of rest and remain hydrated. Painkillers may also be used if muscle pains become too uncomfortable.

The Field of Remembrance ceremony is not the first public engagement that Camilla had to cancel due to her chest infection. Earlier, the duchess was also absent from the gala dinner for Prince Albert’s 200th birthday, which was held at the London Library.

Camilla Parker Bowles and Prince Charles 2012 06 05 - the Diamond Jubilee Balcony at Buckingham Palace - Camilla and Charles. Keith Laverack/Flickr