The family of Hoku Award-­winning singer Malani Bilyeu is grieving again.

Just five weeks after Bil­yeu, a founding member of the contemporary Hawaiian band Kalapana, died of a heart attack, his son Travis Isobe died in a head-on crash on Kauai over the weekend.

Crystal Bilyeu said her son had the biggest heart.

“Family was always first for him,” she said.

Isobe, 28, died Saturday night after a pickup truck slammed into the truck he was driving on Kuhio Highway in Kilauea.

Police said a white Dodge pickup truck operated by a 22-year-old Kilauea man was traveling south on the highway when for unknown reasons it crossed the centerline and struck head-on a black Ford Ranger pickup truck driven by Isobe.

He was pronounced dead at the scene. The crash occurred shortly before 9 p.m. near the Kahili Makai Street junction.

Police said the Dodge driver sustained non-life-­threatening injuries and was taken to Wilcox Medical Center where he was treated and released.

Police arrested him Monday on suspicion of first- degree negligent homicide in connection with Saturday’s crash. He was released pending further investigation.

Angelei Castillo said her nephew was helping his seven younger siblings cope with their father’s recent death.

“And now you have this,” she said. “You get in shock over a tragedy and you have another one. It takes your breath away.”

“It’s mind-boggling,” she added. “You’re just suspended in shock.”

On the night of the crash, his younger siblings were waiting for him to come home to play a board game together.

Malani Bilyeu, who died Dec. 27 at 69, raised Isobe since he was just under a year old after marrying Isobe’s mother.

Isobe, a Kapaa High School graduate, served in the Marines from 2014 to 2018. He earned the rank of sergeant and was stationed in California and Okinawa before he returned to Kauai last year to be with his family.

He looked after his younger siblings, Castillo said, adding, “Growing up, instead of going out to play with his friends, he would take care of his siblings.”

He also had a close relationship with Leina‘ala Hatori, Bilyeu’s oldest daughter from a previous relationship.

Isobe developed a bond with his biological father, Alvin Isobe, whom he met when he was 15 years old.

Castillo described her nephew as a strong, soft-­spoken and humble man with a huge heart.

“He was the most humblest person,” she said. “He was a very good example of a very good human being.”

Funeral arrangements are pending.