Two Kankakee County sisters with a condition so rare that only 20 new cases are diagnosed annually in the U.S. created a story about an underwater village.

And the Coal City Middle School band will bring that story to musical life at 7 p.m. Thursday at the Coal City Performing Arts Center.

Annabelle, 9, Beedle, and her sister Abigail Beedle, 5, are planning to attend the concert, according to a news release from Coal City Middle School.

Annabelle and Abigail Beedle both have CLN2, “a rare and incurable genetic condition” that is a form of Batten disease, according to the Ann & Robert Lurie Children’s Hospital in Chicago, where the sisters receive enzyme replacement therapy.

CLN2, typically identified in children between ages 2 and 4, can cause seizures, vision loss and gradually affect cognitive abilities, coordination and mobility – with a lifespan only into the late teens, according to Ann & Robert Lurie Children’s Hospital in Chicago.

Ann Gill, community relations specialist for the Coal City Community Unit School District 1, said in the release that the sisters “embrace each day with remarkable spirit.”

“Their parents, Amanda and Adam, have become strong advocates for advancing research toward a cure and increasing awareness of CLN2 and its impacts,“ Gill said in the release. ”Through their collaboration with Sing Me A Story, the family hopes to center their journey on resilience, love, and the possibility of brighter days ahead."

Matthew Felbein, Coal City’s choral director, transformed the story into an instrumental composition in conjunction with the Sing Me a Story Foundation, the second time Felbein has composed for Sing Me a Story Foundation.

Felbein was a student at the University of Illinois when he composed his first piece, which the Illinois Wind Orchestra presented with narration by the composer.

“The foundation pairs children in need with composers who transform their personal stories into original music,” Gill said in the release. “Those pieces are then shared and performed by school music groups, helping spread the message of healing through music.”

Annabelle and Abigail Beedle created a story about princess sisters who journey in a pink submarine with their feline sidekicks Tigey and Wilbur to an undersea world filled with mermaids, mermen and meranimals, Gill said in the release.

“Unfortunately, their arrival is not welcomed by the mercommunity that is under attack by sharks,” Gill said in the release. “However, with the help of the Mercat, the community comes to understand the princess are there to help them and together they successfully get the sharks to swim away from their undersea town.”

Andrew Brimm, director of the Coal City Middle and Intermediate School bands, initially learned about the opportunity to collaborate with the Sing Me a Story Foundation and he “immediately signed on,” Gill said in the release.

“He saw it as a meaningful way to demonstrate to his students – and the wider community – the powerful, healing impact music can have," Gill said in the release.

Brimm said in the release that the Beedle sisters’ piece “has become a favorite piece for many of our students because of the emotional background and storytelling.”

“Having the opportunity to work closely with a composer on this project has truly been a joy,” Brimm said in the release. “Mr. Felbein has portrayed the story so well through music, and it brings a sense of breath and pulse to make it feel real for the audience and our performers.”

Felbein said Brimm brought the composing opportunity to him. His first experience with the Sing Me a Story Foundation was extremely positive, so he was “all in,” he said.

“I’ve always been in love with movie soundtracks and how those scores tell the story, and my own experiences writing original music for short films helped me with this piece as well,” Felbein said. “The imagination, wonder, and heart that kids put into their own fairytales provided some of the greatest inspiration for me to work with as a composer.”