Tito Jackson, a founding member of the Jackson 5 along with his brothers Jermaine, Jackie, Marlon, and Michael, died Sunday at 70.

An official cause of death has not been confirmed. Longtime Jackson family friend Steve Manning told Entertainment Tonight that he believed Jackson suffered a heart attack while driving from New Mexico to Oklahoma.

Toriano Adaryll “Tito” Jackson was born Oct. 15, 1953 in Gary, Indiana, the third of 10 children. At 10 years old, he began learning how to play the guitar; by 1964, his parents Joe and Katherine Jackson had assembled the Jackson 5 after discovering their children’s innate musical talent. Tito’s younger brother Michael Jackson became the lead singer of the group, who went on to sign with Motown in 1969.

Though Tito was a talented guitarist, Motown didn’t allow him to perform on any of the Jackson 5’s studio recordings, instead enlisting session musicians. The Jacksons instead signed with CBS Records in 1976, which allowed them more creative freedom to write songs and perform instruments. Along with older brother Jackie Jackson, Tito was arguably the Jackson 5’s most consistent and active member throughout the ’80s, as Michael embarked on his explosive solo career. The quartet of Tito, Jackie, Jermaine, and Randy released the final Jackson 5 album 2300 Jackson Street in 1989, going on hiatus shortly thereafter. They were inducted into the Rock And Roll Hall Of Fame in 1997.

Outside of the Jackson 5, Tito worked as an occasional session musician, producer, and performer in a blues band. He didn’t release a solo album of his own until 2016’s Tito Time, which spawned the mildly successful single “Get It Baby” featuring rapper Big Daddy Kane. His second and final solo album Under Your Spell arrived in 2021.

Revisit a few of the Jackson 5’s hits below.