"They love the water – Charlene saw to that," the royal tells PEOPLE

Credit: Eric Gaillard/Reuters/Landov

As Monaco’s Prince Albert celebrates 10 years on the throne with a grand celebration this weekend, the royal dad is looking ahead to a family summer vacation.

“We’re staying at Roc Agel [the family ranch high above Monaco] and we’re fortunate, we don’t have the kids in our room with us,” he tells PEOPLE of 7-month-old twins Gabriella and Jacques, his children with wife Princess Charlene.

“Charlene gets up a little earlier than I do,” he says. “And she starts her day with them. For my part, I try to give them their last feeding at night. Then I see them in the morning before I go off to work. I try to see as much of them now as I can because they are growing so fast.”

Asked about the babies’ latest milestones, he says with a smile, “They’ve just read the Declaration of Independence and they’re going onto the Bill of Rights next. Am I being too proud as a father?”

When they’re not, ahem, studying up, the twins “are pretty good at sitting up now, and there’s signs of crawling but we haven’t quite gotten there yet.”

One skill they have begun to master early? “They’re almost swimming. They love the water. Charlene saw to that,” he says of his wife, 37, a former Olympic swimmer who has been called "the mermaid of Monaco".

“They’ve some small floatation devices and they’re in the wading pool,” he adds. “And I promise you we’re gonna see some swimming before the summer is out.”

As for readying their children for a life of royal duty, “There are things they will have to learn, and it’s not always a case of sitting them down in an office or schoolroom, saying ‘Don’t do this! Don’t do that!’ I hope to be able to import to them the things which are important.”

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Although he notes, “I haven’t always had the time to be with the children as much as I’d like,” he says he sees his older children, Jazmin Grace, 23, and Alexandre, 11, regularly and will spend time with both this summer.

As for the twins, Albert says he plans to take them to visit the elephant sanctuary established two years ago by his sister Stephanie. The compound, which provides a safe haven for a pair of rescued elephants, Baby and Nepal, is opposite the entry to Roc Agel, “but Jacques and Gabriella haven’t actually seen them yet,” he explains.

“We kind of whisk them by. Showing them the elephants is part of our summer plan.”

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