Conrad Bain, the Canadian-born actor who played the adoptive father of two young African-American brothers in Diff'rent Strokes, has died. He was 89.

Bain died Monday of natural causes in Livermore, Calif., according to his daughter, Jennifer Bain.

Lethbridge, Alta.-born Bain had a stage and screen career that included the role of uptight neighbor Dr. Arthur Harmon on 1970s series Maude.

On screen, he often was cast in the role of the erudite gentleman or kindly father. In Diff'rent Strokes, which debuted 1978 and starred the late Gary Coleman and Todd Bridges, he was the straight man to Coleman’s comedian.

Bain didn't mind being overshadowed by the focus on the show's children. He praised Coleman and Bridges as natural talents without egos.

Diff'rent Strokes is remembered partly for its child stars' adult troubles, which Bain sometimes discussed in interviews as he continued to be involved in their lives.

Coleman had financial and legal problems in addition to continuing ill health from the kidney disease that stunted his growth. Bridges and Dana Plato, who played Bain's teenage daughter, both had arrest records and drug problems. Plato died of an overdose in 1999 at age 34.

Bridges started to put his drug troubles behind him in the early 1990s, telling Jet magazine that Bain had become like a real father to him.

Born Feb. 4, 1923, Bain studied at the Banff School of Fine Arts and served in the Canadian army during the Second World War. He had a twin brother Bonar, who once played a fictional "evil" twin to him on an SCTV episode.

Conrad Bain studied at the American Academy of Fine Arts in New York, with classmates such as Charles Durning and Don Rickles.

He had stage roles in New York in The Iceman Cometh, Candide, Advise and Consent, An Enemy of the People and Uncle Vanya, according to IMDB.

Conrad Bain, left, played Philip Drummond, the kindly adoptive father to Todd Bridges and Gary Coleman. They are shown at 1981 Emmy Awards. (Associated Press)

In 1958, he played at the Stratford Shakespeare Festival in A Winter's Tale, Much Ado About Nothing and Henry IV, Part I. He acted with a Seattle repertory company before moving into television in the late 1950s. He returned to the stage frequently throughout his life.

His TV career began on the New York-shot soap opera Dark Shadows, where he was eaten by a werewolf. He also had a role in The Edge of Night before his first significant series TV role in Norman Lear's Maude.

That part as Rue McClanahan's stuffy, conservative doctor/husband who often clashed with the feminist Maude marked him as a comedy actor and led to Diff'rent Strokes. Later he had another series, Mr. President, alongside George C. Scott.

He had minor roles in films such as Woody Allen's Bananas (1971), Sean Connery's The Anderson Tapes (1971), Barbra Streisand's Up the Sandbox (1972) and Postcards from the Edge (1990).

One of his last on-camera appearances was reprising his Philip Drummond role from Diff'rent Strokes on a 1996 episode of The Fresh Prince of Bel-Air.

Bain married artist Monica Marjorie Sloan in 1945 and they had three children. Monica died in 2009 and Bain is survived by children Jennifer, Kent and Mark.