A Mount Carmel High School student died after collapsing Tuesday afternoon while he played basketball at a South Side YMCA.

William Gibson, 15, of the 2900 block of S. King Dr., was playing basketball with friends when he collapsed at the facility on the 6400 block of S. Harper, near his school.

Mount Carmel athletic trainers attempted to revive the teen. They were told he had a pre-existing condition, possibly an enlarged heart, officials said.

He was pronounced dead at 4:38 p.m. at Jackson Park Hospital, according to the medical examiner's office.

Gibson was not a member of the school's basketball team. Mount Carmel Athletic Director Frank Lenti said the sophomore "always had a smile on his face."

"When I did see him around the P.E. classes or gym he seemed likable," Lenti said.

A photo of Gibson with the phrase "Forever In Our Hearts" was placed on the school's website.