Kate Middleton joins Prince William and Prince Harry at the Queen's birthday Easter service - best photos

On Sunday, the royal family had double to celebrate as they stepped out to attend the Easter Sunday church service at St George's Chapel in Windsor, which coincided with the Queen's 93rd birthday. The Duke and Duchess of Cambridge were in attendance, as were Prince Harry, and Zara and Mike Tindall. The Queen – who is Head of the Church of England – looked lovely dressed in a vibrant outfit, and was all smiles as she made her way to the chapel. Three out of four of her children were also there, with Princess Anne, Prince Edward and Prince Andrew all in Windsor for the morning.

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Over at Buckingham Palace meanwhile, the Band of the Irish Guards will perform a rendition of Happy Birthday in honour of her majesty. Earlier in the day, the 93-year-old was wished many happy returns by her family on social media, including the Duke and Duchess of Sussex. The royal couple were praised for sending such a personal message, complete with handpicked photos of the pair with the Queen.

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This is the Queen's first of two birthdays. She also has an official one on the second Saturday in June each year, which is celebrated with the Trooping of Colour parade. Gun salutes are also fired as a mark of respect to the Queen on her special day - but never on a Sunday, so this year they will be delayed by one day.

The royal family were all out to celebrate the Queen's birthday on Sunday. The Cambridge family are close to Zara and Mike Tindall, who they recently met up with during the Easter holidays.

The Duchess of Cambridge and Zara Tindall looked like the best of friends as they linked arms outside St George's Chapel.

Princess Beatrice looked lovely in a blue printed dress and matching accessories as she walked alongside her dad, Prince Andrew.

The monarch was surrounded by many members of her family on her special day. 

Prince Harry attended the church service alone while his pregnant wife, the Duchess of Sussex, stayed at home closeby in Frogmore Cottage to rest.

The Duchess of Cambridge looked as stylish as ever in a blue dress with a co-ordinating coat and hat, which she teamed with a pair of nude heels. 

Prince Harry was all smiles at the Sunday church service, looking smart in a navy suit on her grandmother's special day. 

The Queen looked lovely in a turquoise coat and matching hat as she attended the Easter Sunday church service on her birthday. 

Princess Anne was joined by Timothy Laurence and her two children, Zara and Peter, along with their partners Mike and Autumn. 

Mike and Zara Tindall enjoyed a morning with the royal family, including the Queen, Princess Anne and Autumn and Peter Phillips.

Kate showed her impressive curtsy skills in front of the royals and the Queen as they stood outside St George's Chapel. 

Sophie, Countess of Wessex co-ordinated with daughter Lady Louise Windsor, with the pair both wearing pretty floral dresses.

The Duchess looked in great spirits as she smiled at the Queen outside the chapel. 

The Duke and Duchess of Cambridge lead the way as the royal family headed towards St George's Chapel.