Kate Middleton Gives Rare Update on Queen Elizabeth After She Skipped Church Service Due to 'Discomfort'

Kate Middleton Gives Rare Update on Queen Elizabeth After She Skipped Church Service Due to 'Discomfort'

Kate Middleton is giving a health update on Queen Elizabeth after she skipped an appearance during her Platinum Jubilee celebrations.

During a reception held at Guildhall by the former Lord Mayor on Friday, the Duchess of Cambridge, 40, told an attendee that the Queen was "fine" after a long day of Trooping the Colour.

"Yes, she [the Queen] was fine, it was just very tiring yesterday," Kate said, according to PA, adding that the monarch "had had a lovely, lovely time."

The palace also confirmed on Friday that the Queen, 96, will not be attending Saturday's Derby at Epsom Downs amid her recent mobility issues.

On Thursday, the palace first announced that Queen Elizabeth would be taking a break during her four-day Platinum Jubilee celebration after a whirlwind day of Trooping the Colour celebrations left her feeling "some discomfort."

Queen Elizabeth, kate middleton
Queen Elizabeth, kate middleton

Chris Jackson/Getty

The monarch attended a beacon lighting ceremony on Thursday evening but was absent from the national service of thanksgiving in her honor at St. Paul's Cathedral on Friday.

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"The Queen greatly enjoyed today's Birthday Parade and Flypast but did experience some discomfort," a spokesperson for Buckingham Palace said.

RELATED: Queen Elizabeth Pulls Out of Jubilee Appearance After Experiencing 'Discomfort' at Trooping the Colour

Queen Elizabeth II Jubilee then and now
Queen Elizabeth II Jubilee then and now

Chris Jackson/Getty Queen Elizabeth

"Taking into account the journey and activity required to participate in tomorrow's National Service of Thanksgiving at St Paul's Cathedral, Her Majesty with great reluctance has concluded that she will not attend," the statement continued.

"The Queen is looking forward to participating in tonight's Beacon lighting event at Windsor Castle and would like to thank all those who made today such a memorable occasion."

A source told PEOPLE that the Queen's episodic mobility issues flared during the course of the day on Thursday. She was pictured using her cane on the palace balcony as she took the salute and viewed the flypast alongside members of the royal family.

The Duke and Duchess of Cambridge leaving the National Service of Thanksgiving
The Duke and Duchess of Cambridge leaving the National Service of Thanksgiving

PA Images / Alamy Stock Photo Prince William and Kate Middleton at St. Paul's Cathedral

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It's a regrettable but sensible decision based on the physical demands of tomorrow's service at St. Paul's Cathedral, the source added. It was always the Queen's hope that she would attend rather than a firm commitment.

The Queen has been experiencing mobility issues in recent months and finds it difficult to stand for long periods. She has been using a walking cane and even complained about mobility problems, joking during an in-person meeting: "Well, as you can see, I can't move!"