Taci Belisle knew early on something wasn't right with her son, Ryder.

He was diagnosed with Autism, but Taci sensed there was something more.

For two exhausting years, she researched.

Taci traveled from her home in Sedro-Woolley to Tacoma last year, finally finding a doctor who would listen.

"The doctor looked right at him and right away knew what he had," said Taci.

Ryder was diagnosed with Sanfilppo syndrome, a rare and fatal genetic disorder that affects just 1 in every 200,000 children.

"It was actually a relief to find out exactly what was going on ... and then it hit me that my child was not gonna live," said Taci, choking back tears.

Ryder is just three years old. He may not see his 16th birthday.

"No parent should have to bury their child," said Taci. "I think about that."

VIDEO: 'Ryder's been fighting since the day he was born'

Doctors say, eventually, Ryder's brain will forget all of the progress he has made. He won't be able to walk, or even crawl. He'll forget how to swallow and eventually how to breathe.

It's much like Alzheimer's disease, except when it starts to hit Ryder he will likely be just 5 years old.

"Either his functions go in a week or they go over a period of time," said the mother of three.

Taci has been holding fundraisers and events to raise awareness of the disease. She knows time is growing short for her son, as it will for so many others.

She has the words "never giving up" tattooed on her arm. To her, those words as permanent as the love written on her heart.

"I want everyone to know that I'm never giving up, no matter what. I will keep fighting for a cure for these kids."

To find out more about Ryder's story, Sanfilippo syndrome and fundraising efforts check the family's Facebook page.