Cameron Diaz hits new territory after blonde movie roles

AFTER years of playing the ditzy blonde known for having one of the broadest smiles in Hollywood, Cameron Diaz is moving on.

Following roles in comedies such as Charlie's Angels and last year's What Happens In Vegas, she admits that it was new territory acting in the big-screen adaptation of Jodi Picoult's heart-wrenching novel My Sister's Keeper.

Reflecting on her portrayal of mother Sara Fitzgerald, whose child is dying from leukaemia, she explains that she had to grow into the role.

"There was a certain level of maturity that had to come with playing this role," she says.

In the film, Fitzgerald has a second child by IVF as a blood and marrow donor for her first daughter Kate.

The movie co-stars 13-year-old Abigail Breslin as the youngest daughter Anna, who sues her parents for the medical rights to her own body, when she's expected to donate a kidney to her sister Kate (SofiaVassilieva).

Cameron, 36, admits it was a "touchy" role to take on, but she felt ready for it: "It was a nice stepping stone in the experience of life."

Casting Cameron as a mother of three teenage kids is an unusual choice for any director, but Nick Cassevetes, who won critical acclaim for 2004's The Notebook, thought otherwise. He picked her because she had done so little drama, saying: "I really didn't want to cast an actress who had done something similar for this film."

And Cameron hasn't let him down.

"I feel like Sara is a warrior," she gushes. "She doesn't have a moment not to be vigilant. She has a child who's dying and she has been through a decade of this vigilance. So, she's just sort of pushing through this."

To research the role, Cameron met mothers with sick children who were going through the same thing as Sara.

The film throws up the moral quandary of whether it's right to have a child as an organ donor for a sick sibling.

Cameron says she didn't make the film as a "moral statement" and that in her discussions with parents, the unanimous answer was that it would be a "tough decision".

"But, ultimately, you cannot make the decision to let a child die. It goes against every fibre of a parent," she adds.

Cameron is full of praise for her young co-stars.

"First off, Abigail and Sofia are both total pros,"she says, blue eyes sparkling.

Cameron gets an equally glowing report from the two girls, who say she took on a "motherly role" on set and off set, making snacks for the cast in her trailer.

California-born Cameron grew up on the golden beaches of San Diego and became a model after leaving high school at 16.

She got her first acting break at 21, when she auditioned for The Mask. But it was There's Something About Mary that made her name as a comic actress.

Over the next 10 years, she worked her way up to become the highest-earning woman in Hollywood.

Today, she's passionate about her family - and says the film echoes her bond with her older sister Chimene.