Kate Middleton’s Dress and Hat Debuted During the Royal Ascot Race Has Twitter Talking

Kate Middleton and husband Prince William joined Queen Elizabeth at the Royal Ascot on Tuesday, an annual five-day horse race and one of the most anticipated events on the Royal Family’s social calendar.

Twitter lit up with glowing reviews of Middleton’s cornflower blue dress with sheer sleeves by Elie Saab, paired with a matching Philip Treacy hat with a flower detail. Blue topaz and diamond drop earrings by Kiki McDonough finished off the monochrome look.

“She looks stunning,” one Twitter user wrote.

“Love Kate in blue. That hat!” another said.

“Love that Queen Elizabeth and Kate BOTH went for the light blue today at the Royal Ascot!” another fan wrote, referencing the queen’s blue dress.

“Spotted: William and Kate looking picture perfect as always!” someone else said.

“I love Duchess of Cambridge’s Elie Saab dress,” another user wrote.

Blue seemed to be the color of choice for several members of the royal entourage, with the queen, Princess Beatrice, Princess Eugenie and Zara Tindall all wearing various shades at the event.

The Duke and Duchess of Cambridge were among the guests on the first day fo the horse racing festival that the queen, who wore a blue coat and matching flower hat by Angela Kelly, attends every year with her family and friends. She hosted King Willem-Alexander and Queen Maxima of the Netherlands in her lead carriage that processed onto the course, with Prince Andrew completing the foursome.

Also joining the queen were her granddaughters Princess Beatrice and Princess Eugenie, who were in the fourth carriage. The sisters shared the carriage with the queen’s private secretary Edward Young and one of the Queen’s cousins Princess Alexandra. Eugenie’s husband of eight months, Jack Brooksbank, was not at the race.

Also missing from the grand event were Prince Harry and Meghan Markle. While the Duchess of Sussex made her first official post-baby appearance at Trooping the Colour earlier in the month, she’s still officially on maternity leave and is likely at home at Frogmore Cottage in Windsor with 1-month-old son Archie.

“Meghan is on maternity leave, but Trooping is a family occasion,” a source told PEOPLE as to why Markle attended the event despite her maternity leave. “You don’t skip the Queen’s birthday. She’s the queen!”

It’s possible that royal watchers will see Harry attend the Royal Ascot with Markle later this week.