Prince Frederik of Luxembourg passes away from rare genetic disease

Prince Frederik, the son of Prince Robert of Luxembourg and Princess Julie of Nassau, passed away on March 1 in Paris, France. He was in his early 20s.

Prince Robert announced the untimely passing of his son in a statement posted on the website of the POLG Foundation, an organization founded by Frederik in 2022 for POLG patients.

“It is with a very heavy heart that my wife and I would like to inform you of the passing of our son, The POLG Foundation Founder and Creative Director, Frederik,” Prince Robert wrote. 

Recalling the events before his passing, Prince Robert said that Frederik "called us in to his room to speak to him for one last time" on February 28, "Rare Disease Day." 

"Frederik found the strength and the courage to say goodbye to each of us in turn — his brother, Alexander; his sister, Charlotte; me; his three cousins, Charly, Louis, and Donall; his brother-in-law, Mansour; and finally, his Aunt Charlotte and Uncle Mark," his father wrote.

Frederik was born with POLG Mitochondrial disease, a rare genetic disorder that “robs the body's cells of energy, in turn causing progressive multiple organ dysfunction and failure,” according to the POLG Foundation.

“He had already spoken all that was in his heart to his extraordinary mother, who had not left his side in 15 years,” Prince Robert continued, referring to his wife Princess Julie.

“After gifting each of us with our farewells – some kind, some wise, some instructive – in true Frederik fashion, he left us collectively with a final long-standing family joke. Even in his last moments, his humour, and his boundless compassion, compelled him to leave us with one last laugh… to cheer us all up."

According to Prince Robert, they didn’t know about Frederik's disease at the time of his birth and he was diagnosed with POLG at the age of 14.

In the statement, the royal detailed the last question his son asked him, which was, “Papa, are you proud of me?”

"He had barely been able to speak for several days, so the clarity of these words was as surprising as the weight of the moment was profound. The answer was very easy, and he had heard it oh so many times… but at this time, he needed reassurance that he had contributed all that he possibly could in his short and beautiful existence and that he could now finally move on."

Prince Robert also described Frederik as their "superhero," saying that one of his superpowers was "his ability to inspire and to lead by example."

"Frederik passed on March 1st 2025, in Paris France, the City of Lights. One light was extinguished, but so many remain," he wrote.

"We wish to extend our deep gratitude for all the messages of support and love received by our family in this very difficult moment. With our Superhero’s help we hope to turn our deep grief into positive results and therewith follow his unwavering example. His ultimate message is one of hope, compassion, and resilience!"

— Jade Veronique Yap/CDC, GMA Integrated News