George Osmond, patriarch of the Osmond family of singers including Donny and Marie, passed away Tuesday of natural causes at age 90, a family spokesperson said.

George Osmond, the man that managed his children’s career into becoming a huge musical act in the 1970s, died Tuesday of complications related to old age at his home in Provo, Utah, said family spokesman Kevin Sasaki.

It was almost half a century ago that George Osmond, a father of nine children, helped his talented progeny sign a deal with singer Andy Williams that would launch a successful and extensive career for the siblings.

“He was a man of integrity, of honor. He was the best man I've ever known,” daughter Marie Osmond, who is a contestant on “Dancing With the Stars,” told “Entertainment Tonight” on Tuesday before joining brother Donny for the flight to Utah.

It was George that taught four of his sons, Alan, Wayne, Merrill and Jay, to perform as a barbershop quartet. A fortuitous trip to Disneyland in the early 1960s saw the boys give an impromptu performance at the park. They were hired to perform regularly and the rest is history.

A short while later they joined singer Andy Williams on his show; they debuted on “The Andy Williams Show” in 1962. Donny joined the group a year later, when he was only six, the Los Angeles Times reports.

Having the Jackson 5 as inspiration, the Osmonds released their own debut album in 1970. They soon had a hit with “One Bad Apple (Don't Spoil the Whole Bunch)” which catapulted them to stardom. Marie began appearing with the group in 1973. Three years later, Donny and Marie had their own show on ABC, with their siblings appearing as well.

George Virl Osmond, born Oct. 13, 1917, in Star Valley, Wyo., was a devout Mormon. He went on missions for the Mormon Church in Hawaii and Britain. Osmond served in the Army during World War II.

He married Olive May Davis in 1944. They had nine children. The eldest sons, Tom and Virel, did not perform with their younger siblings, due to degenerative hearing disorders that affected their speech, according to the Times. This led Osmond and Olive to form a foundation nowadays known as the Children's Miracle Network. Olive Osmond died a few years ago.

Osmond and Olive are survived by nine children, 55 grandchildren and 48 great-grandchildren.