THE COLONY -- For Penny and Dustin Howard, the last few days have been a blur.
"They've been pretty rough. It was a shock," Dustin said.
"We had no idea she wasn't going to come home," Penny said.
5-year-old Harper has been in and out of the hospital all her life, battling a rare disease called CDKL5. It's a genetic disorder only 900 people in the world have ever been diagnosed with.
Last week, they headed to the hospital with what they thought was a respiratory infection.
"Which she has had before," Dustin explained. "She's come out of it fine. She's been in some bad shape before, and she's come home. But there was some stuff going on on a metabolic level."
"Ultimately, what she died from was the metabolic component to CDKL5," Penny said.
The chemical imbalance that ultimately killed Harper wasn't something they could have predicted, but her parents are grateful for the quality of life they were able to give their daughter during the last two years of her life.
"The blessing in all of it is that we were able to stop the seizures and because of that, over the last 28 months, we've been able to get to know her," Penny said.
What stopped the seizures was hemp oil -- a controversial treatment that put an end to up to 15 seizures a day. Instead, Harper was seizure-free."She could interact with the family.
"She could interact with the family, she interacted with her sister, could shake her head yes, could shake her head no, tell you what she like what she didn't like," Penny explained.
Doctors encouraged her parents to keep using the hemp oil, which comes from the cannabis plant and contains almost no THC.
It's legal in all 50 states.
Harper's journey has changed the lives of thousands of sick children across the globe, like Katiele Fischer who's child has CDKL5, from Brazil. She ended up getting hemp oil legalized there using Harper as proof it worked.
And this little girl's legacy doesn't end with her death.
"We made sure that would continue by donating her body to science. She's the first CDKL5 brain to be banked for research," Penny said.
Yeah, the fight against CDKL5 will continue and Harper Howard is giving folks hope for a cure.