Kate Mara Steps Out with Husband Jamie Bell and Sister Rooney Mara at L.A. Fundraiser for Chimpanzee Rescue

Kate Mara had her nearest and dearest by her side as she celebrated a cause close to her heart.

The actress was joined by husband Jamie Bell and sister Rooney Mara as they stepped out to attend the Liberia Chimpanzee Rescue & Protection (LCRP) reception in West Hollywood, California, on Wednesday, Dec. 4.

The organization oversees the care of rescue chimps who were previously used as lab animals or were the victims of the illegal bushmeat and pet trades.

Kate, 41, and Bell coordinated in dark-colored attired, with the Chappaquiddick actress in a black blazer-style jacket and her Rocketman actor husband, 38, in a black suit jacket over a dark T-shirt.

Rooney, 39, was similarly dressed, smiling in a shot with her sister in a dark blazer over a white shirt as the two embraced for the camera.

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Related: Rooney and Kate Mara Fighting to Save Forgotten Lab Chimps

According to LCRP's official website, the organization "​is the first and only chimpanzee sanctuary and conservation center in Liberia rescuing chimpanzees who are victims of the illegal bushmeat and pet trades."

"With over 100 orphaned chimpanzees, most still babies or children, are currently under the care of LCRP," they add. "Each month, more captive chimpanzees are confiscated, allowing for the enforcement of Liberia's wildlife laws. Without the ability to confiscate wildlife, authorities cannot protect and preserve chimpanzees."

Kate and Rooney are longtime advocates with the group, having traveled to Liberia in 2018 to learn more about the work of Jim and Jenny Desmond, the founders of LCRP in West Africa.

"Once we had the opportunity to be face-to-face with these incredible animals, there was just no turning back," Kate told PEOPLE in December 2020.

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Related: All About Kate Mara and Jamie Bell’s Relationship: From Meeting on Set to Their Private Family Life

Kate — who welcomed a daughter in May 2019 and a son in November 2022, with husband Bell — distinctly remembered her first encounter with the chimps.

"They're very similar to human babies. At first, we made sure to really give them their space and let them come to us until they were ready to explore," she told PEOPLE in December 2020. "But what was really spectacular was when we went back two years later, they immediately remembered us."

"Which is outrageous. That would never happen with a human baby. It just goes to show how spectacular these animals are," Kate continued.

The actress added of BBC America’s Baby Chimp Rescue, which features LCRP's team caring for 38 baby chimps in its third episode, "Hopefully, when people see these chimps, it will inspire and teach them about these animals ... and then it opens their eyes to all animals in need."

Read the original article on People