‘Child influencer’ who inspired £10m fundraiser for rare disease research dies aged five

A five-year-old boy whose parents documented his journey with a rare disease has died aged five.

Jelte passed away at home in his mother Sanne’s arms in the early hours of Wednesday (17 Jun), with the rest of the family sleeping around him.

He suffered from metachromatic leukodystrophy (MLD), a rare inherited disorder that affects the brain’s white matter, leading to a progressive loss of physical and later cognitive abilities.

Sanne told Dutch media at the end of 2024 that there had initially been no signs that anything was wrong with Jelte.

It was only when he was still not walking after his second birthday, began falling frequently and developed a squint that she became concerned.

A genetic test confirmed he had MLD, a condition that typically limits life expectancy to around five to seven years.

A five-year-old boy with a rare brain disease who became the face of a Dutch fundraising campaign has died at home in his mother's arms - his family helped raise €11m for research. — *Jelte. (Picture: Jam Press)*

Jelte’s parents set up an Instagram account in April 2023 to document his journey and raise awareness of the disease.

They also used it to mark milestones such as his “monthly birthdays”, as well as sharing moments from everyday life with his sisters, Veerle and Linde, and the family dog Tibbe.

By the time of his death, the account had more than 23,000 followers, as reported by Need To Know.

At the end of 2024, Jelte became the face of the Glass House fundraising campaign, part of the Dutch radio initiative 3FM Serious Request in the city of Zwolle.

The campaign went on to raise more than €11m (£9.53m) for Metakids, a charity funding research into metabolic diseases in children.

Sanne told local media at the time: “Last year hardly anyone knew anything about metabolic diseases.

“I hope that by 1 January 2025 everyone will know about them and that an enormous amount of money will be raised for research. It feels like a kind of legacy from Jelte.”

The family’s situation worsened in early February 2025 when Jelte’s father, Hein, was diagnosed with diffuse large B-cell lymphoma, a type of non-Hodgkin lymphoma affecting the throat.

His first symptoms appeared in late December 2024, beginning as a persistent sensation of something stuck in the throat, followed by reduced running fitness and increasing breathlessness.

The cancer is considered highly treatable, with an estimated survival rate of around 85%.

In a post announcing Jelte’s death, Sanne wrote: “Since 11pm last night (16 Jun), we had noticed that Jelte was beginning to say goodbye to life. We kept vigil by his side for two hours before eventually falling asleep.

“When everything was quiet, Jelte found his final rest. It is incredibly sad, but it happened in a very beautiful way.

“He had earned his rest and was truly ready for it.”

The Municipality of Zwolle said: “His strength, openness and cheerfulness moved the whole of the Netherlands to raise money for Metakids. We are extremely grateful to him and to all donors for that.”