INDIANAPOLIS -- While advancements in medicine are too late to help their children, a central Indiana couple are at the forefront of advances in research that will benefit children suffering from a rare disease.

Phil and Tricia Milto's children, Nathan and P.J., both have Late Infantile Batten Disease, a progressive disease that robbed them of their childhood.

"They have respiratory issues, and we fight those daily," said Phil Milto. "We try to care for them the best we can."

The boys must have care around the clock, and it's become a way of life for their parents, 6News' Stacia Matthews reported.

"They don't talk or communicate with us that way, but with their eyes, the strokes they give us, we know they're happy and appreciate their family and all of their friends," Milto said.

6News first went to the Milto home nearly 10 years ago, when Nathan was 5, before the rare neurological disorder slowly took his eyesight, motor skills and cognitive abilities.

Three years later, Nathan's brother P.J. received the same crushing diagnosis.

In 2001, there was no way to stop or slow the disease that threatened to kill the boys. A search for answers led their parents to create a foundation to raise money for research.

"The disease has been slowed, even stopped in the children, therefore providing very positive results, and that was one of our main goals -- to let all the wonderful people in Indianapolis who have supported us through the years know … that we have done what we set out to do," Milto said.

The Nathan Battle Foundation raised more than $5.6 million for a study at Cornell University. The boys volunteered for an experimental gene therapy procedure in which doctors injected enzymes depleted by the disease back into their brains.

"Our study has been published formally into medical journals, thus creating more validation for the process and providing evidence and proof that our drug … works," Milto said.

The study caught the attention of scientists around the world who are now testing the drug to treat other children with Batten Disease and adults with Parkinson's Disease.

"It's great to see others benefits from the work that our community has done around the world," Milto said.

A newer version of the drug is showing promising results in lab animals.

"They live longer. They live almost normal life spans, which has never been demonstrated before," Milto said.

The bright light of hope is a gift from the family of two boys who will never see the full results themselves.

Nathan and P.J. are both blind. They can't walk or talk. The new medicine has slowed the progression of their illnesses, but the disease is already too advanced for them to lead normal lives. The Miltos know that Nathan and P.J.'s battles are far from over, but they feel blessed that the boys' illness spurred action that prompted results.

"They are heroes in my mind and champions for everyone who's gone through this devastating issue," Milto said.