Nicole Kidman stepped out for a good cause, four days after she filed for divorce from Keith Urban.

The actress, 57, attended amFAR’s Dallas auction in Texas on Saturday, Oct. 4. The event was held in support of the nonprofit’s work to support AIDS research and prevent the spread of HIV worldwide.

News first broke Monday, Sept. 29, that Kidman and country musician Urban, 57, separated in early summer after 19 years of marriage.

When Kidman filed for divorce on Sept. 30, she cited irreconcilable differences and listed the former couple’s date of separation as the time of filing.

Nicole Kidman speaking about Taylor Sheridan at amfAR

Nicole Kidman on Oct. 4.

Other notable attendees at the amFar event include actress Teri Hatcher, Yellowstone creator Taylor Sheridan, Diana Ross and Dallas Mavericks legend Dirk Nowitzki. Kidman presented Sheridan, 55, with the night’s Award of Inspiration at the event. (The pair work together on Lioness.)

Hatcher, 60, hosted the auction, which took place at the home of United Airlines CEO Scott Kirby.

Nicole Kidman arrives at the 2024 Governors Awards at Dolby Theatre on November 17, 2024 in Hollywood, California; Keith Urban attends the 2025 Academy of Country Music Awards press room at The Ford Center at The Star on May 08, 2025 in Frisco, Texas.

Nicole Kidman; Keith Urban.Steve Granitz/FilmMagic; Taylor Hill/WireImage

Kidman and Urban married in 2006 and share two daughters, Sunday Rose, 17, and Faith Margaret, 14. Kidman asked to be the primary residential parent in the custody agreement as part of the divorce filing.

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“She’s been stressed because she knew the separation would eventually become public and she was dreading it,” a source close to the family told PEOPLE of Kidman on Oct. 2. “But she’s surprisingly level-headed and calm. Now that it’s out, she’s just focused on what’s ahead and her girls.”

On Sept. 29, an insider told PEOPLE that Kidman had been “fighting to save the marriage,” even amid the pair’s private separation in recent months.

“She didn’t want this,” the insider said, noting that “the entire Kidman family has come together to support one another,” particularly Kidman’s sister Antonia. Antonia and the Oscar winner were spotted on a walk together on Wednesday, Oct. 1, which marked Kidman’s first sighting since the news of her divorce first broke.