Princess Charlene of Monaco, Prince Jacques of Monaco, Princess Gabriella of Monaco and Prince Albert II of Monaco.Photo:Stephane Cardinale - Corbis/Corbis via Getty

Princess Charlene of Monaco, Prince Jacques of Monaco Princess Gabriella of Monaco and Prince Albert II of Monaco

Stephane Cardinale - Corbis/Corbis via Getty

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 ofPrince Rainier III, who, with wifePrincess Grace, founded the country’s modern dynasty.

This year’s annual event also included a balcony reunion of over two dozen royal nieces, nephews and their children.Can’t get enough of PEOPLE’s Royals coverage?Sign up for our free Royals newsletterto get the latest updates on Kate Middleton, Meghan Markle and more!

Princess Charlene of Monaco and Prince Albert II of Monaco.Stephane Cardinale - Corbis/Corbis via Getty

Princess Charlene of Monaco, Prince Jacques of Monaco Princess Gabriella of Monaco and Prince Albert II of Monaco

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.

Princess Charlene of Monaco and Prince Albert II of Monaco.Pascal Le Segretain/Getty

Princess Charlene of Monaco, Prince Jacques of Monaco Princess Gabriella of Monaco and Prince Albert II of Monaco

Pascal Le Segretain/Getty

With National Day falling on a Sunday this year, mass wasaugmented 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.

Princess Charlene of Monaco, Prince Jacques of Monaco, Princess Gabriella of Monaco and Prince Albert II of Monaco.David Niviere/SC Pool - Corbis/Getty

Princess Charlene of Monaco, Prince Jacques of Monaco Princess Gabriella of Monaco and Prince Albert II of Monaco

David Niviere/SC Pool - Corbis/Getty

Never miss a story — sign up forPEOPLE’s free daily newsletterto stay up-to-date on the best of what PEOPLE has to offer, from celebrity news to compelling human interest stories.The National Day ceremony traditionally opens the Monaco holiday season.

He’ll be home in time for his twins' birthday in December, and will then join them at theannual 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.

source: people.com