Barbara Sinatra, widow of Frank Sinatra, dies at 90

Barbara Sinatra, philanthropist and wife of the legendary singer Frank Sinatra, died on Tuesday. She was 90. John Thoresen, director of the Barbara Sinatra Children's Center, told CNN that Sinatra died of natural causes. She was surrounded by family and friends at her home in Rancho Mirage, California.  The former model and Las Vegas showgirl married Sinatra in 1976 and was the last of his four wives. The couple were married for 22 years when the singer died of a heart attack in 1998. Theirs was the longest lasting of the singer's marriages.