Shirley MacLaine Is What Warren Beatty Needed to Get Marriage to Annette Bening ‘Back on Track’

Siblings Shirley MacLaine and Warren Beatty have been hanging out plenty since she relocated from New Mexico to Malibu – and it’s helped improve the actor’s shaky marriage to Annette Bening , a source exclusively reveals to Closer .

“She’s always thought of Warren as her kid brother,” the source says. “She adores him and clucks over him tirelessly.”

Warren, 87, and Annette, 66, married in 1992, which came as a surprise to most fans considering the Bonnie and Clyde actor’s public and well-documented history as a Hollywood Lothario.

“It’s no secret Warren and Annette have had their ups and downs of late, but Shirley’s positivity and practical advice have been the treatment they needed to get back on track.”

The pair first met when Warren was casting Bugsy – he knew of Annette from her film debut in The Great Outdoors and thought of her first for the role. He even declared to the director, Barry Levinson , "I love her, and I'm going to marry her," after inviting her to lunch following her audition.

He never wavered from his absolute assuredness about marrying the American Beauty .

"When you're older and you meet somebody,” he told Robert Ebert in 1994, “the decision-making process is a lot shorter.”

“And that happened here and I listened to it," he said. "And by listening to it, it enabled me not to question it too much...and I never did."

More than 20 years later, he echoed the same sentiment.

"It didn't really surprise me,” the actor told hosts on Today in November 2016. “I had no doubt when I met Annette that it was time to get married.”

However, their whirlwind romance forced Annette to confront some difficult choices and, despite being set to play Catwoman in Tim Burton ’s Batman Returns , she dropped out of the film to start a family with Beatty, whom she was not married to, but dating at the time.

There was also the lingering reputation as a womanizer Warren had accrued throughout his Hollywood career to overcome.

When asked about how they kept their marriage together for so long, Annette, speaking exclusively to Closer , said, “There is no secret, as anyone who has been married knows.”

“ We’ve been through a lot. ”

Luckily, the long-time Hollywood leading man has his Oscar-winning sister, Shirley , 90, to look out for him.

“Shirley’s all about good karma and that’s what Warren and Annette need to hear,” the source tells.

Shirley pulls no punches when she needs to keep Warren in line.

“I was lucky to grow up with a feminist mother and a feminist sister ,” Warren told People , “We’re very close.”

“She’s good at cracking their heads together in a loving way. She sticks up for Warren and with Annette,” the source says.

“She’s had a very good relationship with Annette and thought she was the perfect gal for her sibling and still does,” the source continues.

“She’ll do everything in her power – and she knows where to go for that! – to keep these two together.”