Sienna was cast as the wife of Dylan Thomas after Lindsay Lohan pulled out of the movie

She recently told Elle magazine: "I wish I was Sienna Miller."

"At the parties, I stand on my own, grinning aimlessly. I can never think of a thing to say. I watch that girl and she’s just fabulous. She talks to everyone and laughs and smiles and looks as if she is genuinely enjoying herself.

"When I talk to her I hope a bit of her party personality will rub off on me, but it never does. She could give master classes in being the most amazing party guest."