Patty Duke - the actress best known for her eponymous sitcom and Oscar-winning work on the big screen - has passed away at the age of 69.
Early reports indicate that Duke passed away from sepsis due to a ruptured intestine.
Her family confirmed the news of her death in a statement issued moments ago:
"This morning, our beloved wife, mother, matriarch and the exquisite artist, humanitarian, and champion for mental health, Anna Patty Duke Pearce, closed her eyes, quieted her pain and ascended to a beautiful place," the statement reads.
"We celebrate the infinite love and compassion she shared through her work and throughout her life."
Duke started her career as a child star, winning an Academy Award at the age of 16 for her performance as Helen Keller in The Miracle Worker.
She went on to star as identical cousins on the popular sitcom The Patty Duke show, which ran for more than 100 episodes.
After being diagnosed with bipolar disorder in the early '80s, Duke became an advocate for those struggling with mental health issues.
She continued to work steadily throughout her life, appearing in episodes of Glee and the Disney channel sitcom Liv and Maddie in her final years.
Duke is survived by her three children, including Lord of the Rings star Sean Astin.