Miguel Cervantes, who plays Alexander Hamilton in the Chicago production of the Broadway hit, is preparing to say good-bye to his 3-year-old daughter Adelaide, who suffers from a neurodegenerative disorder, according to People magazine. Cervantes and his wife Kelly told the magazine that she started suffering from seizures at the age of 7 months, and was later diagnosed with Infantile Spasms or I.S. “She is a warrior. I have never met someone stronger in my life,” Kelly told People. “She shared her opinions in her own way.”

The couple first noticed their daughter was regressing after the seizures began. “When we first found out that something was wrong, we started Googling around about infantile spasms, and it was just terrifying,” Miguel told People. “It was then that we also started to notice a loss of ability. Adelaide had always been a thumb sucker. When that stopped, the doctors told us that it wasn’t a sign of the seizures per se. This was a regression within the brain. And we began to realize that this was something that could be terminal.”