My 5-year-old son has dementia, we were told it was autism for years

A mom who suspected there was something more to her son’s autism diagnosis has finally received a heartbreaking answer. 

Tammy, 34, from Swansea in South Wales, believed her son Tate’s challenges could not be fully explained by autism alone.  

“I just knew there was more to it,” Tammy told Newsweek. While Tate was happy, energetic and very content, he didn’t show emotions like her friends’ children did. 

As a first-time mom during the COVID-19 pandemic, Tammy remembers thinking her son was “too good to be true,” given that he didn’t cry and had a laid-back temperament.  

The feeling that something deeper was being missed never left her. It wasn’t until March 2024 when doctors found ventricles—spaces in the brain—which are a sign of childhood dementia, during a CT scan.  

After a long and exhausting search for answers, doctors confirmed that Tate had Sanfilippo Syndrome Type A—a rare and terminal condition often known as childhood dementia.  

The disorder causes progressive neurological decline, and children gradually lose the skills they once had, including the ability to walk, eat and eventually move altogether.  

In Tate’s case, being nonverbal and showing limited emotional expression often mirror autism so closely in the early years that many children are initially misdiagnosed. 

Tammy said that children start to regress at around 5 or 6 and, by the time they are 8 or 9, they might be tube-fed in a wheelchair. 

Tate has never spoken, something that once felt part of his autism diagnosis. Now, Tammy understands that she will never hear his voice, which is painful and heartbreaking.

While there is no cure for Sanfillippo Syndrome anywhere, research efforts continue. Some experimental treatments aim to slow the progression of the disease rather than reverse it.  

In the U.S., there is growing hope that a gene therapy known as UX111 could receive approval by the end of 2026. 

Early trial data has shown that children who received the treatment experienced significantly less regression than those who didn’t. 

While the therapy would not be a cure, it could help protect brain function for longer, slow or stabilize disease progression and improve quality of life.  

Tammy has set up a GoFundMe page to raise money for travel to America and also shares Tate’s journey on TikTok (@tates.tomorrow). 

Overall, sheis fighting for her son’s chance to have a good quality of life. In his last years, it is likely that she will become his full-time carer.  

The thought of Tate not knowing who she is, however, is too much to bear.  

“Time is of the essence,” Tammy said. “The best thing I can do is fight for his quality of life…[but] I’m living in this moment because, at any point this year, it could turn.”