Back to Buckingham Palace! Queen Elizabeth II left a London hospital on Monday, March 4, just one day after being admitted with a stomach bug.

"The Queen has left The King Edward VII's hospital, having been admitted briefly as part of the assessment of symptoms of gastroenteristis," a Buckingham Palace spokesman tells Us Weekly of the 86-year-old British monarch.

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Fittingly regal in a red coat and broach, the Queen smiled as she walked out of King Edward VII hospital (the same place where her grandson's pregnant wife, Kate Middleton, was treated in December for severe morning sickness). According to Reuters, she shook hands with medical staff on the steps of the facility before being driven away in a motorcade.

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Palace sources say the Queen is "in good spirits but will still need to spend the rest of the week resting." (As a result of the stomach ailment, the Palace cleared her schedule for the coming days.) Insiders add that she carried out 425 official engagements last year and has told aides that this hospital trip was a minor "inconvenience." Her next public outing is scheduled for Monday, March 11, when she will carry out Commonwealth-related engagements, including a Westminster Abbey service.

The Queen was taken to the hospital as a "precautionary measure" on March 3 after falling ill two days earlier. "She was not taken into hospital immediately after feeling the symptoms," a palace spokesman said in a statement to the BBC. "This is simply to enable doctors to better assess her."

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Queen Elizabeth's grandsons, Prince William and Prince Harry, meanwhile, spent the weekend in Switzerland, where they attended pal Mark Tomlinson's wedding to Olympian Laura Bechtolsheimer and hit the slopes of the Swiss Alps. On Sunday, March 3, William's wife, Duchess Catherine, offered a glimpse of her growing baby bump when she was photographed walking through the snow in black pants and a loose-fitting blouse.

This article originally appeared on Queen Elizabeth Leaves Hospital After Stomach Ailment