Luxembourg's Prince Frederik, 22, dies due to rare genetic disease

Independent

09-03-2025

The son of Prince Robert of Luxembourg and Princess Julie of Nassau, Prince Frederik, has died at the age of 22.
Robert posted an emotional message on the POLG Foundation's website on Friday to announce his son's death. Frederik also founded the organization, which aims to help find treatments for his rare disease condition, POLG Mitochondrial disease.
'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,' Robert wrote in the lengthy statement. '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.'
'He had already spoken all that was in his heart to his extraordinary mother, who had not left his side in 15 years,' Robert continued, referring to his wife.
After Frederik gave the individual farewells, he left his loved ones 'collectively with a final long-standing family joke.' Before Frederik cheered his entire family up, 'in his last moments,' Robert recalled the last question that his son asked him: '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,' Robert continued. '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.'
Robert went on to call his son his 'superhero,' before praising the work Frederik has done with the POLG Foundation. He also applauded his son's 'superpower,' which was the ability to inspire and lead by example.
'Frederik was born with a special capacity for positivity, joy, and determination. When he was little, I would always say that if there is one child of ours that I would never need to worry about, it was him,' Robert added. 'He has social skills like no other, an amazing sense of humour, an emotional intelligence and compassion that were off the charts, a sense of justice, fairness and decency that knows no bounds. He was disciplined and organised beyond belief.'
Later in the statement, Robert shone a light on POLG Mitochondrial disease, and how the early symptoms are hard to recognize, as in Frederik's case.
'Frederik was diagnosed with POLG at the age of 14, when his symptoms were showing more clearly and when the progression of his disease had become more acute,' he continued. 'Because POLG disease causes such a wide range of symptoms and affects so many different organ systems, it is very difficult to diagnose and has no treatments, much less a cure.'
POLG Mitochondrial disease is 'a genetic disorder that robs the body's cells of energy, in turn causing progressive multiple organ dysfunction and failure,' as noted on the POLG Foundation's website. While the disease is so uncommon that 'no one knows how many patients there are,' symptoms can often include muscle weakness, epilepsy, and liver failure.
Robert concluded his statement about his son by applauding the positivity he had while experiencing symptoms of the rare genetic disorder.
'This is the battle that Frederik fought, and this is the burden that he had to carry throughout his life. He always did so with grace and with humour. When we asked him if he wanted to create a foundation to find a cure and help others like him, he jumped at the opportunity,' the Prince of Luxembourg said. 'Though he always made it very clear that he did not want this dreadful disease to define him, he nonetheless immediately identified with and helped define the mission of The POLG Foundation..'
Along with their son Frederik, Robert and Julie share two other children: Prince Alexander and Princess Charlotte.
The late 22-year-old previously spoke out about his genetic condition. Last year, he was featured in his organization's short film, The PolG Foundation Film, which includes a scene of him watching videos from his childhood.
'When you're a kid, you've got all these dreams, all these aspirations, these things you want to do. The possibilities are endless,' he said in a voiceover. 'I'm not sure I understood all the consequences of PolG when I first got diagnosed. It's more subtle, where slowly, the world is getting smaller and smaller.'
Luxembourg is a landlocked country in western Europe with a population of just 660,000. A constitutional monarchy, it has one of the highest GDP per capita ratings.