Drew Barrymore & Toni Collette Are Your New BFFs

When you're playing best friends on screen - best friends that journey through a difficult cancer diagnosis together, no less - it's hard not to get close during filming.

But for Drew Barrymore and Toni Collette, their on-screen friendship has become something so much more, with the pair admitting they are now best friends in real life.

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"I think the outcome is obvious," says Barrymore, of the friendship they developed during the filming and promotion of their latest film, Miss You Already.

The actresses star as Milly (Collette) and Jess (Barrymore), best friends who have journeyed through life together, but who face their biggest challenge when Milly is diagnosed with breast cancer.

Collette knew that she wanted Barrymore by her side to play her on-screen bestie, going so far as to write the Hollywood star a letter urging her to get involved with the project.

"She is the ultimate girl's girl, she's incredibly talented, she inspires me and she's so grounded and warm," Toni says of her co-star, lovingly reaching across to touch Drew's face.

"She's so much better than I had ever imagined, she exceeded all expectations and I can't imagine going through this journey with anybody else," she smiles.

Barrymore - who rose to fame as the super cute Gertie in E.T. - had no hesitations in taking on the role once she knew Collette was on board.

"I moved my family to London, I said, 'I'm literally here for you, and I have your back and let's do this'," she says.

The pair - who share plenty of mutual celebrity friends - now spend their time travelling together and catching up whenever they can, making them the celebrity girlfriends everybody wants to have.

"We have steak and martinis and just hang out and talk about everything...and it's the best," laughs Barrymore of their 'ultimate girl squad'.

"She can't get rid of me now," laughs Toni.

Miss You Already is in Australian cinemas from October 8, 2015.

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