Prince Albert and Princess Charlene Pose with Their Twins as They Celebrate Monaco's National Day

It was a family affair as Monaco's royals celebrated the country's National Day.

Monaco celebrated the annual occasion on Sunday, which commemorated the centennial of Prince Rainier III, who, with wife Princess Grace, founded the country's modern dynasty.

Drawing together three generations of the royal family, Prince Albert and Princess Charlene were joined by their 8-year-old twins — son Prince Jacques and daughter Princess Gabriella — plus Albert's sisters, Caroline, Princess of Hanover, and Princess Stephanie.

This year's annual event also included a balcony reunion of over two dozen royal nieces, nephews and their children.

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Monaco's National Day began with a solemn early morning Te Deum mass for 1,900 invitees. Arriving at the Cathedral, Prince Albert, 65, was dressed in uniform with military honors, while Princess Charlene, 45, came head to toe in national red. 

Sporting a double-breasted redingote with a wide rolled collar that was decorated by a single ribboned medal, the Princess paired the attire with a custom Stephen Jones beret-style hat and high-heeled boots. 

With National Day falling on a Sunday this year, mass was
augmented with elements of the Monaco Symphony, as well as clarions from the principality's Carabinieri orchestra.

Returning to the Palace, Prince Albert and Princess Charlene proceeded to the courtyard ceremonies, which are part of the annual festivities.

Dressed in deep midnight blue, Princess Gabriella wore an outfit almost identical to her mother's — right down to her Stephen Jones beret. Prince Jacques, meanwhile, wore a uniform and cap, matching his father.

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The National Day ceremony traditionally opens the Monaco holiday season. 

This week, the family will celebrate Thanksgiving (a family meal introduced by Princess Grace), before Prince Albert departs for three state visits in Asia ahead of attending the COP28 conference in Dubai. 

He'll be home in time for his twins' birthday in December, and will then join them at the annual palace gift day (another Grace legacy).

Afterwards, the entire family will pack their bags for an end-of-the-year winter holiday in the Antarctic.