The There's Something About Mary actress is reportedly 'done' with Hollywood and has no plans to return to acting.
Selma, who starred alongside Cameron in 2002 comedy The Sweetest Thing, spoke out at the Oscar's Vanity Fair pre-party about doing a potential sequel for the movie.
'I would have liked to do a sequel but Cameron's retired from acting, she's like "I'm done",' said the Cruel Intentions star.
'I mean, she doesn't need to make any more films, she has a pretty great life, I don't know what it would take to bring her back.'
Cameron has been on a break from acting since her last movie, Annie, which was released in 2014.
Shortly after filming Annie, the 45-year-old met Benji Madden and married him in a top-secret ceremony in 2015.
Us Weekly reported Cameron was more interested in settling into family life than her continuing her film career.
In an interview with Andy Cohen in 2016, she opened up about their marriage: 'It was one of those things where everyone tells you, "You just know when you know". I was like, "What does that mean?" Oh, I get it. You just know when you know. Like you're my husband.
'No one compares. Everything else just like washes and slips away. You realise like, "Oh this is like the real thing is. This is what real love is. This is what real commitment and devotion is. This is the person you build your life with".'