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Reese Witherspoon finds herself in the middle of a love triangle in This Means War, and we were with the Oscar winner when she was just 15 working on her first feature film!

In September of 1991, ET caught up with confident up-and-comer Reese on the set of her coming-of-age flick The Man in the Moon, in which she plays a young girl in late 1950s Louisiana who falls for a boy three years older than her (played by Jason London) at the same time as her older sister.

Reese started acting at age seven in commercials, and by the time she was a teen the Hollywood attention seemed to be a little overwhelming.

"It's tough sometimes, because people want to make you have these big decisions and stuff – do you want to do this script, do you want to do that? – and it's tough," she said, adding with a laugh, "Finally, I just kind of sit down and say, 'I don't know. I'm 15 years old. You figure it out for me.' I don't know. There's so many things I don't know about."

Watch the video to hear Reese share details about her first kiss -- and what she plans to do for her future kids!