Lynn Shelton, the beloved indie film director who also helmed mainstream TV programs like “Little Fires Everywhere,” “Mad Men” and “GLOW,” tragically died on Friday. Her publicist cited a previously unknown blood disorder as the cause of death. She was 54.

Shelton made her directorial debut at the Sundance Film Festival in 2006 with “We Go Way Back” but it was her second feature film, “Humpday,” starring Mark Duplass and Joshua Leonard, that opened up doors for the Seattle native. She would later reunite with Duplass on “Your Sister’s Sister,” led by Emily Blunt and Rosemarie Dewitt, and also worked with Duplass on the drama “Outside In,” while Dewitt would pair up with Shelton again in 2013’s “Touchy Feely.”

Shelton most recently directed four episodes of Hulu’s “Little Fires Everywhere,” starring Reese Witherspoon and Kerry Washington. She also helmed “The Mindy Project” and nine episodes of ABC’s “Fresh of the Boat,” among other TV shows.

Several of the director’s collaborators and fellow filmmakers took to Twitter on Saturday to express their disbelief and sadness.

Witherspoon posted a photo of her and Shelton on Instagram, saying “I’m in complete shock that this vibrant, talented, and soulful filmmaker is no longer with us.”

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I’m so devastated to hear about Lynn Shelton’s passing yesterday. I’m in complete shock that this vibrant, talented, and soulful filmmaker is no longer with us. Lynn was so passionate about our show, Little Fires Everywhere. She said the book truly spoke to her, and that she longed to direct a show that spoke meaningfully about motherhood, sexuality, race, and class in America. And she did. She cared deeply about the WHOLE cast and crew, making sure we all felt heard, seen and appreciated. Lynn also shared so much of her life with us. Her love of her son, how motherhood changed her life, her life changing decisions that made her the woman she was. I feel so fortunate that I got to collaborate with Lynn on both The Morning Show and Little Fires Everywhere. Her spirit touched so many people in the filmmaking world. Her memory lives on in our vivid days together on set and in her wonderful films. Please watch her work and see her talent for yourself. #RestInPeaceLynn 🙏🏻💫💜

A post shared by Reese Witherspoon (@reesewitherspoon) on

“Her boundless creative energy and infectious spirit were unrivaled,” Duplass wrote. “She made me better. We butted heads, made up, laughed, pushed each other. Like family. What a deep loss.”

Mindy Kaling, who worked with Shelton on “The Mindy Project,” wrote: “Lynn Shelton loved actors and we loved her back. She was a dream on set. Her lovely, sunny energy was infectious and actors always drifted to video village between takes to be around her. She had such a quiet power and I will miss her. Rest In Peace, Lynn. Love you.”

“Such a shocking and devastating loss,” Alison Brie, star of “GLOW,” said on Twitter. “I’ll miss you, Lynn.”

Ava DuVernay first met Shelton in 2012 when she handed DuVernay the Sundance filmmaker prize for “Middle of Nowhere.”

“Lynn Shelton changed my life when she handed me the Directing Award at Sundance in 2012,” DuVernay wrote. “She announced my name with pride. Handed it to me with love. Rooted for me long after. I can’t believe I’m typing this. Rest In Peace, Beauty. Thank you for your films. And for your kindness.

Drake Doremus, helmer of Sundance films such as “Like Crazy” and “Douchebag,” wrote: “I’ll never forget seeing humpday at Sundance ‘09. Never went for the joke and always felt so genuine. It observed the human spirit in the most naturalistic of ways. It inspired me a lot. Lynn inspired me. You will be missed by many.”

“I am truly shocked at the passing of Lynn Shelton,” noted Edgar Wright, director of “Hot Fuzz” and “Baby Driver.” “She was a friend, a kind heart, so talented & only just getting started, despite her stellar work so far. My heart goes out to her family and loved ones. She’s left us too soon. I can’t believe I’ll never hear her laugh again.”

See other tributes below:

https://variety.com/2020/film/news/lynn-shelton-death-sundance-filmmakers-mark-duplass-mindy-kaling-alison-brie-reese-witherspoon-little-fires-everywhere-kerry-washington-1234608673/