Sandra Bullock's longtime partner Bryan Randall has died. He was 57.

After a three-year battle with amyotrophic lateral sclerosis, or ALS, Randall died Aug. 5.

"Bryan chose early to keep his journey with ALS private and those of us who cared for him did our best to honor his request," Randall's family said in a statement to USA TODAY on Monday. "We are immensely grateful to the tireless doctors who navigated the landscape of this illness with us and to the astounding nurses who became our roommates, often sacrificing their own families to be with ours."

According to Mayo Clinic, ALS is a "nervous system disease that affects nerve cells in the brain and spinal cord." The disease causes "loss of muscle control" and "gets worse over time."

The Oscar-winning actress met the model-turned-photographer when he was hired to capture her son Louis' birthday party in 2015. The two started dating shortly after and were spotted out and about by paparazzi before they made their red carpet debut at the "Our Brand Is Crisis" premiere in Los Angeles in October of that year, according to Today.

Together, the couple were parents to three children: Bullock's adopted kids Louis Bardo and Laila, and a daughter Randall had from a previous relationship.

Randall's family added Monday that "at this time we ask for privacy to grieve and to come to terms with the impossibility of saying goodbye to Bryan."

Bullock, 59, star of movies such as "Mis Congeniality" and "The Blind Side," previously was married to reality TV star and automotive fabricator Jesse James. The couple married in 2005 but split in 2010 after multiple women came forward claiming that James had relationships with them during his marriage to the actress.

After rumors swirled of Bullock and Randall's relationship status, representatives of the couple confirmed in 2018 they were not married. Later that year, they were spotted at the afterparty for the premiere of her movie, "Ocean's Eight."

In a 2021 episode of the talk show "Red Table Talk," Bullock gushed about her relationship with Randall.

"I don't wanna say do it like I do it, but I don't need a paper to be a devoted partner and devoted mother," she said, adding, "I don't need to be told to be ever present in the hardest of times. I don't need to be told to weather a storm with a good man."

In the same interview with hosts co-hosts Willow Smith, Jada Pinkett Smith and Adrienne Banfield-Norris, Bullock spoke about raising Black children, the challenges they face, and her esteem for her partner and their method of co-parenting.

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"He's the example that I would want my children to have," Bullock said. "I have a partner who's very Christian and there are two different ways of looking at things. I don't always agree with him, and he doesn't always agree with me. But he is an example even when I don't agree with him."

In 2022, while promoting her movie "The Lost City," Bullock told Entertainment Weekly that it was time to step back from film roles in order to focus more on her family life with Randall.

"Right now, and I don't know how long (a break) will be, I need to be in the place that makes me happiest," she said. "I take my job very seriously when I'm at work. It's 24/7 and I just want to be 24/7 with my babies and my family."

In lieu of flowers, Randall's family asked for donations to be made to the ALS Association and the Massachusetts General Hospital, per People and Today.

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