LOS ANGELES – Conrad Bain, the actor who played a white millionaire who adopted two African-American boys on the NBC comedy “Diff’rent Strokes,” has died. He was 89.

Bain’s daughter Jennifer said Bain died of natural causes in Livermore, Calif., where he had moved to a nursing home a few years ago. Bain reportedly died Monday.

“Diff’rent Strokes,” which started its run on NBC in 1978 and ended in 1986 on ABC, was popular mainly due to young co-star Gary Coleman, who played the mischievous Arnold Jackson, one of the two sons adopted by Bain’s character, the patient widower Phillip Drummond. Drummond was the regular straight man to the wisecracking Arnold.

In interviews, Bain said he was discovered by producer Norman Lear, who cast him as conservative neighbor Dr. Arthur Harmon in “Maude,” the comedy about an outspoken liberal that premiered in 1972. Before that, he had been a journeyman actor for two decades, appearing in the original Broadway production of Leonard Bernstein’s “Candide” and off-Broadway in Jose Quintero’s revival of Eugene O’Neill’s “The Iceman Cometh.”

“I thought ‘The Iceman Cometh’ was a total bomb,” Bain said in a 1991 interview with the Los Angeles Times. “We opened on a Tuesday and I told my wife we could make a date for Friday. I guess I was too close to the forest to see the trees.”

Bain at that time was uncomfortable talking about the various personal tragedies that had befallen his three “Diff’rent Strokes” co-stars: Coleman, Dana Plato and Todd Bridges.

Coleman, whose legal and health woes were the stuff of tabloid fodder, died after a brain hemorrhage in 2010. Plato died in 1999 after an apparent drug overdose. Bridges, the sole surviving member of the trio, would later say that sexual abuse in his childhood drove him into a spiral of drug addiction; in 2012, he supported California legislation he hoped would protect child actors from sexual predators.

“It’s painful,” Bain said. “It is really painful. It leaves you with such a helpless feeling. I have been asked to go on all these talk shows and I just think the continued public discussion … I can’t bear the thought. I love them all.”

In 1991, he appeared at the Pasadena Playhouse in a production of A.R. Gurney’s “The Dining Room,” playing various roles from a dying father to a senile old man to a 5-year-old child.

“Somebody said to me, ‘You were the father of all those children on ‘Diff’rent Strokes’ and now you are playing the children.’

In addition to his daughter Jennifer, Bain is survived by sons Mark and Kent.