Photo Credit: Getty Images
Prince Frederik of Luxembourg, the youngest son of Prince Robert and Princess Julie of Nassau, passed away on March 1, 2025, following a courageous battle with POLG Mitochondrial disease. He was just 22 years old.
Born with this rare genetic condition, Frederik wasn't officially diagnosed until age 14, when his symptoms became more pronounced. According to the POLG Foundation, which Frederik himself established, the disease "robs the body's cells of energy, causing progressive multiple organ dysfunction and failure."
In a heartfelt statement published on the foundation's website, Prince Robert described his son's final moments, which occurred symbolically on Rare Disease Day, February 28. "Frederik found the strength and courage to say goodbye to each of us in turn," Robert wrote, noting that Frederik had already spoken privately with his mother, who "had not left his side in 15 years."
Family members gathered for individual farewells, including his siblings Prince Alexander and Princess Charlotte, three cousins, brother-in-law, aunt, and uncle. True to his character, Frederik's last collective message to his family was a long-standing family joke—a final gesture to lift their spirits.
"Frederick is my superhero, as he is to all of our family," Prince Robert stated, emphasizing his son's exceptional qualities. "He has social skills like no other, an amazing sense of humor, an emotional intelligence and compassion that were off the charts."
Prince Frederik spent his childhood in Aix-en-Provence, France, and briefly lived in London before his family settled in Switzerland in 2004. He attended schools including Geneva's International School and St. George's School in Clarens.
Despite living with his condition, Prince Robert noted that Frederik always handled his challenges "with grace and humor." When approached about creating a foundation to help others with POLG disease, "he jumped at the opportunity," though "he always made it very clear that he did not want this dreadful disease to define him."
The young royal's death comes during a period of transition for Luxembourg's royal family. His father's cousin, Grand Duke Henri, announced in December that he will abdicate the throne in favor of his son Guillaume on October 3, 2025, after 25 years of reign.
