Kara Kennedy, daughter of the late Sen. Ted Kennedy, died of a heart attack on Friday, a family aide told CNN Saturday. She was 51.

Kara Kennedy, daughter of the late Sen. Ted Kennedy, died of a heart attack on Friday, a family aide told CNN Saturday. She was 51. (Getty Images)

(CNN) -- Kara Kennedy, daughter of the late Sen. Ted Kennedy, died of a heart attack on Friday, a family aide told CNN Saturday. She was 51.

Kennedy suffered the attack following her daily workout, according to a statement from the Edward M. Kennedy Institute for the United States Senate.

She was the only daughter of Sen. Kennedy, a liberal stalwart who passed away in 2009. That year, Kara Kennedy accepted a Presidential Medal of Freedom from President Barack Obama on behalf of her ailing father.

In 2003, she was diagnosed with lung cancer but overcame the disease.

"Kara was a warm and caring person. Her children were the light and joy of her life," the statement from the institute said. "Her magnificent strength in her successful battle with lung cancer was a quiet inspiration to all of us and provided her family and fellow patients with hope."

Kara Kennedy was a filmmaker and television producer, according to the institute. She also served on the National Advisory Board of the National Organization on Fetal Alcohol Syndrome and as a director emerita and national trustee of the John F. Kennedy Library Foundation.