Duchess Kate looks spring-ready in baby blue for Easter service on the queen's 93rd birthday

The royal family is celebrating Easter, which doubles as the queen's 93rd birthday.

Queen Elizabeth II was all smiles during an Easter Sunday service at St. George's Chapel at Windsor Castle. She donned a pastel blue coat, a bright pink dress and matching hat, a trend among the royals, while holding a vibrant floral bouquet.

Sunday is the first of two birthday celebrations each year for the queen, a tradition that dates back more than 250 years to King George II. She marks her official birthday in June with the Trooping the Color parade.

The matriarch was joined by Prince William and Duchess Kate, who matched the queen in an spring-ready, baby blue coat dress by Alexander McQueen and a gray fascinator.

Queen Elizabeth II departs the Easter Sunday service at St George's Chapel on April 21, 2019, in Windsor, England.
Queen Elizabeth II departs the Easter Sunday service at St George's Chapel on April 21, 2019, in Windsor, England.

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The couple's three children – Prince George, Princess Charlotte and Prince Louis – did not attend. Maybe they were home waiting on the Easter Bunny?

Britain's Prince William and Duchess Kate attend the Easter Mattins Service at St. George's Chapel, at Windsor Castle in England on April 21, 2019.
Britain's Prince William and Duchess Kate attend the Easter Mattins Service at St. George's Chapel, at Windsor Castle in England on April 21, 2019.

In a sweet moment captured ahead of the service, Kate elegantly curtsies as the queen (aka, the birthday girl) arrives at the chapel.

Duchess Kate curtsies as Britain's Queen Elizabeth II arrives to attend the Easter Mattins Service at St. George's Chapel.
Duchess Kate curtsies as Britain's Queen Elizabeth II arrives to attend the Easter Mattins Service at St. George's Chapel.

Prince Harry was also in attendance, without Duchess Meghan, who is expecting the couple's first child any day now. The Duke and Duchess of Sussex did, however, send a birthday salute to the queen on Instagram Sunday.

"Happy Birthday Your Majesty, Ma’am, Granny," the couple wrote on their newly launched Instagram page, which has acquired 4.9 million followers in less than a month. "Wishing you the most wonderful day! Harry & Meghan."

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Elizabeth is the longest-reigning monarch in British history. She still maintains an active schedule, although she does not travel as often as she used to.

Her 97-year-old husband, Prince Philip, has retired from public duties and did not attend the service.

Contributing: The Associated Press

This article originally appeared on USA TODAY: Duchess Kate looks spring-ready in baby blue for Easter service on the queen's 93rd birthday