Prince Albert on His Surprising Neighbors — Sister Princess Stéphanie's Elephants!: 'She Takes Great Care of Them'

Prince Albert of Monaco‘s yard is a bonafide zoo, with two large animals roaming around the grounds of his palace retreat.

“They’re not in the front yard,” Albert tells PEOPLE of the family’s exotic visitors. “Technically, it’s the backyard at Roc Agel. The only problem is I thought they would be temporary.”

The “they” that Albert is referring to are his sister Princess Stéphanie‘s two (fully grown!) rescue elephants, Baby and Nepal.

The elephants are retired circus performers, and the pair became a European cause celebre before Stéphanie stepped in. In 2010, after testing positive for tuberculosis, the elephants were scheduled for euthanasia. Though their diagnosis later proved false, a four-year long legal effort to prevent their deaths failed.

So at the last moment, with encouragement from her children, Stéphanie offered Baby and Nepal a royal reprieve and a place to live — in her brother’s backyard — on a mountaintop above the Principality of Monaco.

Today, the pair — who are 42 and 43 years old — roam their private reserve (a spacious 110-acre park) where they share a savannah-like mountaintop with the Grimaldi family ranch, Roc Agel. Stéphanie exercises with them daily and a team of handlers see to their needs. Baby and Nepal — whose new home includes areas of shaded grove and their own bathing area — have settled in above the French Riviera without complaint.

They are pampered and “they are in great shape,” Albert says. “Stéphanie takes great care of them.” And though they’ve stayed longer than he originally anticipated, the Prince still celebrated the fourth anniversary of their arrival on July 13, with Stéphanie and her children Louis Ducruet and Camille Gottlieb, as well as donors from the Baby and Nepal Foundation.

Baby and Nepal have also found fans in Prince Jacques and Princess Gabriella, Albert’s 2-year-old twins, who “visit across the road regularly and know what elephants are now.” The siblings are animals lovers themselves: Their own farmhouse menagerie includes dogs, chickens, cows and llamas.

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Despite the fact that his oversized neighbors aren’t going anywhere anytime soon, the prince is proud, and thinks their presence has been great for his younger sister.

“It’s given Stéphanie a different understanding of wildlife,” he says. “She was always interested in animals, always had a lot of dogs. Still does. Big dogs. But I think she needed this kind of project. I think it came along at a time in her life she needed something to occupy her energy after her kids had started to move out. It’s an empty nest syndrome,” he suggests with a smile.

He adds: “Filled with elephants, maybe but it’s not a facade. She’s up there practically every day working with them.”