Margaret and Jeremy Bennett's son died in February, but they still listen to his heartbeat every day.

As 14-year-old Dylan Bennett lay dying in the intensive care unit of Cincinnati Children's Hospital, Brian Schreck recorded his heartbeat. He then paired rhythmic thumping with some of Dylan's favorite music to create a song for the Bennetts to keep.

"Our son was dying in front of us, and it was very tough," Jeremy Bennett said in a short film about the songs. "So just to hear that music, it really, really got my spirits up and I needed that."

Over the last six months, Schreck has made a dozen songs for the families of dying patients at Cincinnati Children's Hospital to help them cope with loss, he told ABC News.

He said families worry that they'll forget the feel of their loved ones after they die, and he wants to preserve their "humanity" through music.

Music therapist Brian Schreck makes songs using dying patients' heartbeats at Cincinnati Children's Hospital. (Credit: Courtesy Cincinnati Children's Hospital)

He said the songs vary just as much as the patients, and has included music by artists from John Legend to Metallica. He plays the music himself but leaves the vocals out.

Schreck has been a music therapist for 10 years, but he only recently started making music for patients in the intensive care unit, which he said can be tense.

"People are very on edge all around," he said. "A lot of times, it's quiet when I go into the room, people don't really know exactly what to do or say."

Although there isn't much follow-up, Schreck said he's heard about families playing his heartbeat songs at patients' funerals. And learning that the Bennetts listened to the song he put together for them was incredibly gratifying, he said.

"To let me know that it's in some way helping with their ability to cope with the very early onset of grief is a very rewarding thing," he said.