Avril Lavigne's Alleged Demo of Kelly Clarkson's 'Breakaway' Emerges Online

The song was initially written by Lavigne for his debut album, but it was eventually recorded by Clarkson for the soundtrack of movie 'Princess Diaries 2'.

An alleged demo version of Avril Lavigne's "Breakaway" has landed online in full. The high-quality leaked demo features the pop/rock star singing the song which became a huge hit after being performed by "American Idol" winner Kelly Clarkson as a soundtrack of 2004 movie "Princess Diaries 2: Royal Engagement".

Lavigne initially wrote "Breakaway" for her 2002 debut album "Let Go". The empowering track, however, was sent to the vault after the Canadian songstress deemed it unsuitable for her first LP.

Despite not featuring the hit song, "Let Go" was a big success for Lavigne as it managed to enter Billboard 200's top 10.

Lavigne, who put out her latest album "Avril Lavigne" last year, is currently gearing up to join Backstreet Boys on their "In a World Like This" tour which is set to open in Moncton, NB, on May 3. The tour will hit some Canadian cities before heading to the U.S.

As for Clarkson, the singer who's currently pregnant with her first child released her Christmas album "Wrapped in Red" late last year.