Kristen Stewart "tried to get taller" when playing Princess Diana.
The 31-year-old actress stars as the late royal in the new film 'Spencer' and admits that she wanted to alter her height to match Diana's physical stature.
Kristen told The Sunday Times newspaper: "I tried to get taller.
"I'm 5ft 5in. She had such beautiful stature. I thought, 'I wish I could grow my femur! But I'm playing Diana, I'm not her..."
The movie is set at Sandringham over a weekend at Christmas 1991 and follows Diana's decision to end her marriage to Prince Charles and Kristen was determined to find the "inner fire" of the princess.
The 'Twilight' star said: "She's at her lowest point, but there's still this inner fire. Just don't let it go out."
Kristen also reflected on the way film roles have changed for women as they can be "curious, honest and messy" on screen.
She explained: "We're just allowed to exist now in a way that feels curious, honest and messy.
"Films have been made for a long time by men and you can tell. We are getting to a place, though, where we can destigmatise things that should not be taboo. We've been conditioned our entire lives to go, 'We're OK! We don't feel anything! I don't have cramps right now!'
"If men had periods they'd have two weeks off a month. But, anyway, it's an exciting time to make films, as women can externalise feelings that have been suppressed for ever."
'Spencer' has raised concerns that it could upset Diana's sons Prince William and Prince Harry but Kristen believes that things have changed as the pair have been allowed to make their own "choices and mistakes".
The actress said: "They have been saddled with the burden of our curiosities for their entire lives and that is the job. [Diana's] legacy is clearly in her boys. They have obviously made different choices, but theyíve been allowed to make choices, and mistakes. Whereas, before, choices and mistakes were not to be made. Ever. That is a shift. Whether people admire their choices or not, they are making them."