Olivia Rose Olson (born May 21, 1992) is a singer song-writer and actress based in the United States.

She had her first major acting role at the age of ten in the film ‘Love Actually’ (2003) where she sung a cover of ‘All I Want for Christmas is You’.

In 2007, she debuted as a voice actress in the Disney animated series ‘Phineas and Ferb’ (2007-2015) as recurring character, Vanessa Doofenshmirtz.

Since 2010, she has voiced recurring and fan favourite character, Marceline, on Cartoon Network’s series, Adventure Time, where she has also been able to sing several songs for the show.

In 2013, she released her debut EP Beauty Is Chaos and created a collaboration album with her father titled The Father-Daughter Album of Unspeakable Beauty.

In 2018, Olivia released her debut album Nowhere Land.