LOS ANGELES » Mike Porcaro, who was the son and brother of prominent musicians and carved out a long, successful career as the bass player for the Grammy-winning pop group Toto, has died at age 59.

Porcaro died Sunday, Toto’s publicist Keith Hagen told The Associated Press.

No cause was given, but he had suffered from Lou Gehrig’s disease for several years. He left the group in 2007 because of declining health.

Lou Gehrig’s disease, also called amyotrophic lateral sclerosis, or ALS, attacks the cells that control muscles.

"Mike mentally is fantastic, and if you talk to him, his spirits are up and he’s great and like the old Mike Porcaro, except that he’s disabled, he’s in a wheelchair and can’t move, can’t walk and can’t play, which is a heartbreaking drag," Toto’s keyboard player, David Paich, told the webzine "Something Else" in 2012.

Toto was formed in the late 1970s by Paich, Porcaro’s brothers Steve and Jeff, and other prominent session musicians who have recorded and toured over the years with Michael Jackson, Sonny and Cher, Boz Scaggs, Steely Dan and numerous others.

Porcaro came on board in the early 1980s when bassist David Hungate left to resume his session career.

The three siblings were the sons of jazz percussionist Joe Porcaro. Jeff Porcaro died in 1992.

Toto’s merging of jazz, power-pop, soul and other musical forms sold millions of records in the late 1970s and early ’80s and made the group one of the most popular of that time.

The album "Toto IV" won the Grammy for album of the year in 1982. The song "Rosanna" won record of the year.

Other Toto standards include "Hold the Line" and "Africa."

The group was inducted into the Musicians Hall of Fame in 2009.

Toto’s first new studio album in 10 years, "Toto XIV," is scheduled for release later this month. A European tour is slated for the spring and summer.