Dolly Parton shows no signs of slowing down after more than 50 years in the music industry. In fact, she has recently been working on a songwriting collaboration with Linda Perry, who has written hits for pop stars including P!nk and Christina Aguilera. Perry praises the country legend's tireless work ethic, but the "9 to 5" singer says that she has to keep working in order to prevent her dreams from lying dormant as wishes.

“People ask ‘how do you work all the time?’" Parton shared when she sat on a Leading Ladies Speak Out Panel for the Music Biz conference in Nashville. "Because I dreamed myself into a corner. Now I have to be responsible for those dreams. And I couldn’t be happier, because every dream I have brings on a new dream, like a tree with deep roots and branches and a lotta leaves.”

Recently, that hard work has been in the form of songwriting with Perry to make a soundtrack for the upcoming Jennifer Aniston feature film, Dumplin.' The movie, which is based on a bestselling novel by Julie Murphy, is the story of a plus-sized girl who enters a beauty pageant to show-up her former beauty queen mother. The soundtrack will feature six songs from Parton's illustrious repertoire of hits and six new tunes that she and Perry have been developing together. Some of the songs will be performed as vocal collaborations with Parton and artists like Sia and Miley Cyrus.

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