Queen Elizabeth at the engagement in Windsor Castle on October 19.Photo: ALASTAIR GRANT/POOL/AFP via Getty

She has “reluctantly accepted medical advice” to stay at home to rest at Windsor Castle.
In a statement issued at around 11 a.m. on Wednesday, the palace said the monarch, 95, was in “good spirits.” Her visit was to mark the 100th anniversary of Northern Ireland.
“The Queen has reluctantly accepted medical advice to rest for the next few days,” the statement said. “Her Majesty is in good spirits and is disappointed that she will no longer be able to visit Northern Ireland, where she had been due to undertake a series of engagements today and tomorrow.”
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“The Queen sends her warmest good wishes to the people of Northern Ireland, and looks forward to visiting in the future.”
Queen Elizabeth at the reception on Tuesday evening.ARTHUR EDWARDS/POOL/AFP via Getty

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The Queen’s illness is not COVID-related, PEOPLE understands.
On Tuesday night, alongsidePrince Charles,Prince Williamand other royals, she hosted international business and investment leaders at the castle for a Global Investment Summit reception. Guests includedBill Gatesand U.S. Special Presidential Envoy for ClimateJohn Kerry.
Queen Elizabeth.Jacob King-WPA Pool/Getty Images

She was at Ascot racecourse on Saturday and hadopened the Welsh Parliament, or Senedd, last Thursday, in addition to carrying out aseries of video callsand virtual audiences in the past week or two.
source: people.com