Monaco's Prince Jacques and Princess Gabriella Turn 7 as Dad Prince Albert Reveals Special Birthday Plans

Prince Albert tells PEOPLE a visit to see the twins' mom Princess Charlene is also in the works: "It's what we most hope for"

Princess Gabriella and Prince Jacques. Photo: HSH Princess Charlene Instagram

Monaco's Prince Jacques and Princess Gabriella turn seven on Friday. And as the twins gear up for their birthday party on Saturday, dad Prince Albert has a few surprises in store.

The twins' birthday parties have always been organized by mom Princess Charlene. Previous outings have included a safari-themed party, a museum party with mechanical polar bears, superhero visits and firetruck rides.

This year, however, Charlene is away as she continues her recovery after making a decision to seek medical care after a difficult year. Given Charlene's absence and concerns over COVID, the twins' party will have a more homespun feel, Albert says. (He did offer up a hint of a possible theme: Spongebob Squarepants!)

And while Charlene may not be home for the twins' birthday, a visit for the children to see their mom — even before the holidays — remains the family's priority, Albert tells PEOPLE.

"It's what we most hope for, but there is no definite date at this time," he says.

Charlene shared a sweet birthday message for Jacques and Gabriella in an Instagram post on Friday that included three photos of the twins enjoying an early birthday celebration at the palace.

"Happy birthday my babies. Thank you God for blessing me with such wonderful children. I'm truly blessed. Love mom❤️" she wrote.

In line with existing pandemic precautions, Prince Albert says the twins have been homeschooled at the palace since October.

"Given the uncertainty of the pandemic, Princess Charlene and I preferred to protect them," Prince Albert tells PEOPLE. "So we set up a classroom with the same teachers, classmates, they would have had if they had stayed in their school."

The classroom in the palace's private apartments "is actually in our old childhood nursery. It had since been turned into a home gym, but now it's set up like a normal classroom," he adds. "The kids attend classes with four others."

Supplementing palace lessons are occasional outside gym classes and pool lessons with other children. Going to school at the palace sometimes means crossing the courtyard, which is currently being decorated for the principality's annual Christmas party on December 15.

The Christmas event, which was started by Albert's late mother Princess Grace in 1958, allows every Monagasque child to come to the palace and receive a bespoke gift in person from the prince and members of the royal family.

In keeping with Grace's original theme, which featured Disney cartoons as entertainment, the courtyard has been decorated with giant cartoon figures and tableaux, including Spongebob!

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

The twins' birthday party will be held on Saturday and will also be attended by their four schoolmates and several cousins, according to the prince. And while the kids may suspect a Spongebob party, there will still be lots of surprises in store.

"They'll have seen the Spongebob decorations in one courtyard entrance, so they may have suspicions. But they haven't seen the party room yet," he says.

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A notorious last-minute shopper, Prince Albert conceded earlier this week that he hadn't quite finished wrapping their presents.

"I have a few things in mind," he admits. "To be truthful, I'm working more on their Christmas gifts."