LONDON - Ashlee Simpson says she relates to her role as fame-hungry Roxie Hart in theLondon run of the musical "Chicago." She's been there, done that. "The play is absolutely all about celebrity and wanting to be famous and having your name in the papers and your picture in the papers," the 21-year-old singer-actress told AP Radio in a recent interview.

"And, in that sense, it's been kind of cool because I've really got to connect to that, because I've seen that world and been in that world."

Simpson, whose 2004 debut album, "Autobiography," was a hit despite her "Saturday Night Live" lip-synching snafu, called her new role "extremely humbling."

"You are not a celebrity when you come here," she said. "Everyone is equal, everyone has to work together, so this has been amazing. But, as far as tabloids and whatnot go, I really try to keep my head out of them and try not to read the stories or anything like that, because they are never really true."

Her 26-year-old sister, Jessica Simpson, is also a pop superstar/media magnet. Yet, there's no sibling rivalry, she said.

"Jessie and I don't have that because we're sisters, we've got to be there for each other. We can have the other people we're competitive with, but not each other."