Barbara Sinatra, Frank Sinatra’s Wife, Dead at 90

08/31/2017 04:11 pm EDT

Barbara Sinatra, who was married to music icon Frank Sinatra, has passed away at age 90.

She died on Tuesday at her Rancho Mirage home in California. her health had been declining for months.

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A rep for Sinatra told Desert Sun, "She died comfortably surrounded by family and friends at her home."

Sinatra rose to prominence with Lady Blue Eyes and then went on to become an advocate for victims of child abuse.

She married Frank Sinatra in 1976 and the couple stayed together for almost 22 years. It was the longest of his four marriages.

In an interview, Barbara opened up about her relationship with Frank.

"I've tried to analyze it," she said. "I think it's because we were friends before anything romantic happened. He would call and chat, but it wasn't romantic until later. It's something you can't explain why or how it happened."

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Barbara used her husband's celebrity status and fund-raising abilities to build the Barbara Sinatra Children's Center to help abused children at Eisenhower Medical Center.

John Thoresen, the Children's Center Director, spoke out about her work with the hospital.

"Barbara started raising funds for it in 1985 with Frank's support," Thoresen said. "It opened in 1986 and since that time, over 20,000 children have received beneficial therapy here. There are several child advocacy centers like it around the country, [but] this one is probably most recognized."

A longtime friend, Jamie Kabler, said that the funeral will be held on August 1.

Sinatra is survived by her only child, Robert Marx, and one granddaughter.

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