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rish actress Saoirse Ronan was only 13-years-old when she took the part of a murdered girl who watches over her grieving family in The Lovely Bones. But even at such a young age, she never once worried about playing a dead person.

I never really thought of Susie Salmon as someone who was dead, says Ronan, now 15, of her Bones character. Although her body is dead, her soul is still there. That's what makes Susie who she is and that's what I love about her.

Ronan's performance in the film, which opens in U.S. theaters on Friday and is an adaptation of the best-selling novel by Alice Sebold, seems impressive for such a young woman. Then again, the last few year of Ronan's life have been pretty impressive, too.

The Irish actress (whose first name is pronounced Sir-sha) earned an Oscar nomination for her role as Keira Knightley's younger sister, Briony Tallis, in 2007's romantic drama Atonement.

In Bones, Ronan finds herself carrying an entire movie, with a little help from a stellar cast and crew that includes director Peter Jackson, and Susan Sarandon, Rachel Weisz and Mark Wahlberg as her devastated family.

Despite being adept at handling such heavy subject matter, Ronan seems a typical, carefree teenager. She loves clothes and spending time with her friends back home in Ireland.

I don't see my friends as often as I would like to, so it's always nice to meet up with them, she said. We talk and laugh and listen to music. We also dress up and have a fashion show with the premiere dresses I have at home.

The gown count in her closet is only likely to increase in years ahead. While Bones has earned mixed reviews, Ronan's work has been well-received. There are more films on the way, and Ronan says she expects to make a career as an actress.

MAYBE I COULD DO THIS

After parts in City of Ember and Death Defying Acts, the decision to pursue acting for good crystallized after Atonement, in which she played a young girl who accuses her sister's boyfriend of a crime he did not commit.

'Atonement' was the first film I did that was a real challenge, she says. I was working with some very experienced people. I came out of it feeling like I did a pretty good job and had a good time. The bar was raised for me with acting on that movie. I felt like maybe I could do this professionally.

'Maybe' is modest considering Academy Award voters made her the 11th youngest person ever to be nominated for an Oscar in more than 80 years of giving the world's top film honors.

It is perhaps not surprising to learn that performing runs in Ronan's blood. Born in New York to Irish parents, she moved to Ireland when she was 3-years-old and still speaks with an Irish brogue.

Her father, Paul, is an actor who's had parts in films like The Devil's Own in 1997 and Veronica Guerin. Her parents told her that, when she was a toddler visiting the set of Devil's Own, she was held by cast member Brad Pitt -- although she has no recollection of meeting him.

Yet, Ronan now finds herself traveling in the same Hollywood movie circles as Pitt, working with A-list talent like Sarandon and her next co-star, Colin Farrell, in Peter Weir's war drama The Way Back

But the young actress said she doesn't worry about the trappings of fame, crediting her parents for providing her with a normal childhood in the Irish countryside complete with a dog, a garden and home-cooked meals.

When Ronan works on a film, be it the U.S., England or New Zealand -- where much of The Lovely Bones was shot -- the trio uproots as a unit.

As long as people still want me in their films, I would love to do this for the rest of my life, Ronan says. I have a passion for it. I love it and I have fun.