Patty Duke, best known for her breakout role as Helen Keller in the 1961 film "The Miracle Worker," was a warrior in the eyes of her son.

In an exclusive interview with Entertainment Tonight, Patty Duke's son Sean Astin described his mother as "a warrior," and revealed that she was "at peace" in her final moments. The actress succumbed to sepsis from a ruptured intestine on March 29.

"She was surrounded by her family. It was in the middle of the night and it was a race to get there," he said.

He added that watching his mother in her final moments was a "very powerful experience," and shared how terribly his mother had suffered before her death.

On Wednesday, Astin released a statement on behalf of their family. The statement read:

"This morning, our beloved wife, mother, grandmother, 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. We celebrate the infinite love and compassion she shared through her work and throughout her life."

Patty Duke first played the role of Helen Keller with Anne Bancroft on Broadway. Because of her impressive performance on stage, she was given the same role when the theatrical play was adapted into a film, where she won the Best Supporting Actress in Oscars.

Following her death, photos of the 15-year-old actress with the real life Helen Keller began to circulate online. The photo, taken in 1961, shows the young Duke kneeling down next to the iconic figure while holding her hand.

Sean Astin, who described his mother as "a warrior," will continue to uphold the legacy of the late actress, who is an active advocate for mental health. Recently, he started a Crowd Rise fundraising page to support the launch of The Patty Duke Mental Health Project.