Queen Elizabeth was in good spirits to mark the 100th birthday celebrations of the Royal Air Force on Tuesday

By Erin Hill
July 10, 2018 07:50 AM

Just one day after announcing that she was skipping her great-grandson, Prince Louis’ royal christening, Queen Elizabeth was back in action and in good spirits to mark the 100th birthday celebrations of the Royal Air Force on Tuesday.

The Queen and Prince Philip were noticeably absent from Monday’s christening after the palace made the surprising announcement that the royal couple would not be in attendance. The decision, which was likely due to her busy schedule, was “mutually agreed” upon between the 92-year-old monarch and Prince William and Kate Middleton “some time ago,” a palace source tells PEOPLE.

The monarch just capped off a heavy work week and she has another one in the week ahead. In addition to Tuesday’s day-long event, she will also host President Donald Trump at Windsor Castle on Friday.

Queen Elizabeth on July 10
| Credit: Ray Tang/LNP/REX/Shutterstock

On June 28, the Queen canceled an outing after complaining of feeling sick. The 92-year-old was set to attend a special church service to mark the bicentenary of an order of chivalry but was feeling “under the weather,” a Buckingham Palace spokeswoman said.

Queen Elizabeth
| Credit: Press Association via AP Images

Palace sources say there is no cause for any concern about the health of either her or Philip, 97, who officially retired from royal duties last year. The Queen was lively and all smiles at Tuesday’s event, which began with a service at Westminster Abbey and will continue with an appearance on the balcony of Buckingham Palace.

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The monarch wore a blue silk coat with turquoise detailing over a dress in the same color by her go-to designer Angela Kelly. She paired it with a matching hat by Angela Kelly, a diamond star brooch and her signature pearls.

Credit: Press Association via AP Images
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She was joined by Prince William, Kate Middleton, Prince Harry and Meghan Markle for the celebrations.