Sophie Sartain had long worked in documentary filmmaking as a writer and editor. For her first film as a director, she turned the camera on her own family.

Starting in 2009, she began filming her grandmother Mimi, then 92, who had cared for Sartain's aunt, Dona, for decades. Dona has an intellectual disability and "perhaps some undiagnosed autism," Sartain says. From there the film Mimi and Dona was born. It was released last week on PBS' Independent Lens.

Sartain's grandmother was a "wonderful moving presence" who selflessly devoted herself to caring for her daughter. "Could I be like that?" Sartain wondered. "I'm not that good, I'm not that unselfish. How could I measure up to Mimi?"

But soon she would discover how her own path would overlap with that of her grandmother. "It was during filming that I started to fear my own son might have autism," Sartain says. "And I wondered if I was just beginning a journey that Mimi had just ended."

Her son Ben was diagnosed with autism. Sartain says she saw how her grandmother could be a role model for her and created a second, shorter documentary, Sophie and Ben.

Mimi and Dona is streaming online through Dec. 23.

You can learn more about the film and filmmaker Sophie Sartain by visiting Independent Lens.

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