Ari Schultz passed away peacefully on Friday evening listening to the Red Sox.

Ari Shultz, the five-year old Red Sox fan who went viral this spring after receiving a heart transplant, died on Friday evening while listening to his favorite team, his family announced on Facebook.

On Thursday morning, Shultz had a seizure and returned to Boston's Children's Hospital.

Shultz's heart syndrome was discovered when his mother was 18 weeks pregnant with him. He underwent more than 20 surgeries before receiving a heart transplant in March.

He was a big fan of Xander Bogaerts, who paid him a visit about a month after Shultz was released from the hospital.

Shultz was slated to throw out the first pitch at Fenway Park on August 27.

“I’ve never been around such an uplifting little kid,” Bogaerts told reporters before Saturday's game. “That news, it’s just so sad. He has a special family.”