Tammy McDaid, 34, from Swansea, Wales, says she realised her son Tate, now five, had a rare genetic condition after seeing other children who looked like him on TikTok. Tate was diagnosed with Sanfilippo syndrome, a neurodegenerative disorder often called childhood dementia or childhood Alzheimer's.
Early Signs and Diagnosis
Tammy noticed that Tate rarely cried as a baby, which she thought was "too good to be true." At age two, she took him to doctors for an autism diagnosis due to his lack of reactivity. During the assessment, doctors spotted a bump on his head, and a CT scan flagged potential Sanfilippo syndrome. However, 13 months later, doctors told Tammy that Tate did not have the condition.
Despite this, Tammy remained suspicious after seeing children with Sanfilippo on TikTok who had similar facial features—full lips, a button nose, and coarse heavy eyebrows. She said: "When it was first mentioned, I went on social media and saw other children that looked exactly like my son. But then the experts said it wasn't that so I doubted myself."
Official Diagnosis Confirmed
In August 2025, Tammy was called back for a meeting with a genetic doctor and a metabolic doctor. She said: "We know the NHS is crumbling so they are not going to have two doctors in a room to tell me good news. This is where we were told Sanfilippo was on the table and it could be Type A, the worst one." The official diagnosis of Sanfilippo Type A came in September 2025.
Tammy described the emotional toll: "It took me four hours to do a 45 minute drive home because I was having panic attacks and couldn't stop crying. It was horrible that they took it off the table and then slammed it back on as it put me on a yo-yo for 18 months."
Progression and Treatment
Currently, Tate shows no signs of cognitive decline, but without treatment, he will lose the ability to eat, walk, and communicate. Tammy explained: "The brain damage takes over and he will become completely bed bound and dependent on machines. It completely overrides the body and is the absolute worst way for someone to die."
NHS treatment focuses on pain management. Tammy has given up applying for medical trials, but hopes a revolutionary drug will be approved by the FDA in September 2026. If approved, it would be the first-ever treatment for this rare paediatric disease. According to a Sanfilippo charity, the drug could cost between £1.5 million and £3 million.
Fundraising Efforts
Tammy said: "What hurts me is that I was applying for trials when they first put Sanfilippo on the table, but they closed in August, just before we got the official diagnosis. If the diagnosis wasn't delayed then we could have got into one and life could be completely different." She added: "Once the FDA approves the treatment, the only battle I have is money and the longer that takes, the more Tate deteriorates."
The treatment does not reverse symptoms but should stop further brain damage. Tammy is fundraising through Just4Children, a registered charity. She said: "I live in a world of hope and denial because I have to live in a world where he gets this treatment. I don't look past the end of the year because so much can change in just a few months, but this treatment will allow me to look to our future again."
