Comedic actress Betty White, who capped a career of more than 80 years by becoming America's geriatric sweetheart after Emmy-winning roles on television sitcoms "The Golden Girls" and "The Mary Tyler Moore Show," died on Friday, less than three weeks shy of her 100th birthday.

The agent, Jeff Witjas, told People magazine: "Even though Betty was about to be 100, I thought she would live forever." No cause was cited.

In a youth-driven entertainment industry where an actress over 40 faces career twilight, White was an anomaly who was a star in her 60s and a pop culture phenomenon in her 80s and 90s.