When Megan Kempf noticed her daughter Poppy’s drawings changing, it seemed like a small shift that might pass with time. Poppy had been developing normally, then her mom began to see skills sliding backward instead of moving forward. Kempf, a 37 year old mother in Illinois, said the change was clear in a place many parents would never think to look. “We had noticed that her drawing skills had regressed, she would be able to draw bodied characters, and all of a sudden she would regress to drawing circles.”
At first, the family tried to make sense of the difference between normal childhood ups and downs and something more serious. Poppy was still young, and kids often develop in bursts rather than straight lines. But as she got older, Kempf felt the gap between her daughter and classmates was widening. The concern was not only academic, it was also emotional, as Poppy became increasingly anxious at night. That growing worry pushed the family to keep asking questions instead of accepting simple explanations.
As they searched for answers, doctors identified sleep apnea, a condition where breathing repeatedly stops and starts during sleep. Kempf wondered whether poor sleep was making everything else harder for her child, especially learning and focus. She described being advised to take a wait and see approach when symptoms did not seem dramatic in a single appointment. “I was worried that her sleep apnea may be exacerbating her delays, but nothing was super identifiable or severe so we were being told to wait and see.” For parents, that kind of guidance can feel both reassuring and frustrating, because time matters when a child is losing abilities.
Eventually, the family was referred to a specialist path that included neurology and genetics. Kempf said comprehensive testing finally provided the answer they had been chasing. “We had Poppy’s entire DNA genome sequencing, and that came back testing positive for Sanfilippo syndrome type B.” The diagnosis reframed everything they had been noticing, from the drawing regression to the broader developmental slowdown. It also meant the family had to think about genetics and what it could imply for others in the household.
Because Sanfilippo syndrome type B is inherited, Kempf said they made the decision to test their son Oliver as well. “At that moment, we realised, as it is genetic, that we needed to get our newborn son, Oliver, tested too.” The results brought another devastating confirmation when Oliver also tested positive. For the Kempfs, it meant facing the reality of two children with a rare condition often described as childhood dementia. The label is used because the disease can cause progressive cognitive decline, loss of speech, and loss of motor abilities over time.
Sanfilippo syndrome is linked to the body’s inability to break down certain molecules, including heparan sulfate, due to missing or faulty enzymes. As those substances build up in cells, the brain is especially affected, which is why development can stall and then reverse. Families often describe this stage as a series of quiet losses, where a child slowly stops doing things they once did with ease. In Kempf’s case, the drawings were an early warning, but the impact reaches far beyond art. Over time, the condition can bring sleep problems, behavioral changes, learning difficulties, and increasing dependence on caregivers.
Receiving a diagnosis can bring a strange mix of relief and grief, because finally there is a name for what is happening, but it also comes with a frightening prognosis. Kempf described the shock of hearing doctors talk in terms of life expectancy rather than long term support plans. “Never in a million years did we expect to get a life expectancy for our children.” She also recalled being told there was little doctors could do at present, a statement that many families dealing with ultra rare diseases hear far too often. The feeling of limited options can be crushing, especially when the clock is tied to a child’s age.
Still, the Kempfs have not treated the diagnosis as the end of the story. The family has worked alongside other families to raise money aimed at developing treatments, including enzyme replacement therapy. The effort has already reached $5.5 million, showing how much of rare disease research can be driven by grassroots urgency. While any potential treatment still needs regulatory review, the goal is to move faster than the disease progresses. Kempf summed up the challenge and the hope by saying, “We hope that the medication will be on the market next year, but it will take a lot of attention and effort to get there.”
In the bigger picture, Sanfilippo syndrome is also known as mucopolysaccharidosis type III, often shortened to MPS III. It is considered a lysosomal storage disorder, meaning certain cellular waste products are not processed properly and accumulate in the body. Symptoms commonly appear after early childhood, sometimes after a period of typical development, which is why regression can be such a critical sign. Diagnosis may involve genetic testing, enzyme activity testing, and assessments by neurology and developmental specialists. Because it is inherited, families often speak with genetic counselors to understand recurrence risk and what testing may mean for relatives.
There is currently no universal cure, so care often focuses on managing symptoms and preserving quality of life as long as possible. That can include addressing sleep issues, supporting communication, monitoring mobility, and coordinating therapies that help children stay engaged and comfortable. Research into enzyme replacement, gene therapy, and other approaches continues, and progress can depend on clinical trials, funding, and regulatory pathways. For families, advocacy is not just a side effort, it can become part of daily survival, because awareness drives research interest and research drives options. What do you think families need most when they are fighting rare childhood dementia, and how should communities respond, share your thoughts in the comments.
