Prince Albert of Monaco Reveals How the Royal Twins Are Celebrating Their 6th Birthday Today

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Happy birthday, Prince Jacques and Princess Gabriella!

The royal twins of Monaco turn 6 on Thursday — and their dad, Prince Albert, is spilling all their fun party details.

In years past, the little royals' birthday has been celebrated with a safari theme, mechanical polar bear expeditions and cartoon superheroes at the Palace, sharing cake and bouncy castles with all their classmates.

This year, however, the celebrations will be different amid the ongoing COVID-19 pandemic.

Prince Albert says social distancing and downsized public events are in store for the twins, who will have one scheduled public birthday appearance with a slightly delayed, more intimate celebration at home.

"Their birthday falls on a school day, on a half-day in fact, so our plan is not to have their party that day," Albert tells PEOPLE. Instead, the pair will attend a scheduled outdoor event — "the christening of our new Maritime Police boat, the Princess Gabriella," he says.

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"That should be kind of fun for them," the proud dad says. "Gabriella — she's a pistol, I'll tell you! She's already got a great little sense of humor, sense of showmanship. She's the godmother of that vessel, so she'll preside over the launch ceremony. That should be fun."

"I don't think she's going to actually break a real bottle of champagne across the bow," the son of American princess Grace Kelly adds with a laugh. "She's going to cut a ribbon, for sure, but I have no idea how they'll arrange the traditional bottle christening aspect."

"I've been assured, that there is a way that there won't be any broken glass anywhere near the kids," the concerned dad says.

VALERY HACHE/POOL/AFP via Getty Images Princess Gabriella and Prince Jacques

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On Saturday, mom Princess Charlene has a fun afternoon planned for the kids (birthday cake and candles included!) at Roc Agel, the family compound overlooking Monaco.

"With a limited amount of other children," Albert stresses, "and I emphasize the word 'limited' because they'll be people saying, 'How come they can have a party and our kids can't have group activities?' "

Prince Albert, who tested positive for coronavirus in the spring and recently shared its lasting effects, said there will be a maximum of four other children at the party, including two cousins.

SC Pool - Corbis/Getty Images Prince Albert, Prince Jacques, Princess Gabriella and Princess Charlene

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Considerably smaller than past years, the afternoon party will include nature walk activities and visits to the various farm animals housed at Roc Agel as well as a "surprise" theme.

"It'll be a surprise to me as well because I wasn't allowed to peek in on the planning meeting," he says with a smile.

"As far as gifts, you know, we're still in that age of different games and superheroes, so we're not going to give them anything symbolic or too useful yet. At six, we're still into having fun."