Diff'rent Strokes star Conrad Bain has died just weeks shy of his 90th birthday.

He passed away in Livermore, California on Monday night.

The actor is best known for playing beloved businessman Phillip Drummond, the adopted father of Gary Coleman and Todd Bridges' young characters on the hit U.S. TV sitcom.

His cause of death remains unknown, but Bain's daughter, Jennifer, tells TMZ.com, "He was an amazing person. He was a lot like Mr. Drummond, but much more interesting in real life. He was an amazing father."

Bain would have celebrated his next age milestone on 4 February.

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