Olivia Olson (born May 21, 1992) is an American singer and actress. She is known for her role of Joanna, singing the hit "All I Want For Christmas Is You", in the 2003 motion picture Love Actually.
Olson was born and raised in Los Angeles, California, and lives with her mother, brother and father, well-known comedy writer Martin Olson. She has appeared as a singer and actress on many television shows and has performed live in many Hollywood theaters, including The Comedy Central Stage, The HBO Theater and The Fake Gallery.
Olson has also appeared on The Tracy Morgan Show and was guest star on The Ellen DeGeneres Show singing with Ellen and actor Jack Black.
She is presently a regular cast member of Phineas and Ferb, Disney's unusual animated series, and supplies the voice of Vanessa, the sarcastic daughter of Evil Dr. Doofenshmirtz. She also sings many of the songs in this Disney series.
In the series Phineas and Ferb, she sings the song called "Busted" with High School Musical star Ashley Tisdale. Still in her early teens, she has written songs for Disney's Phineas and Ferb and is presently writing and recording her songs with renowned music producers Rick Nowles, Camara Kambon and Hollywood jazz great Rob Mullins.
According to director Richard Curtis' commentary in the music section of the Love Actually DVD, Olivia's singing was so perfect, they were afraid the audience would not believe that a ten-year-old could really sing the way she did. They had to train her so that her singing would sound more believable.
- On the show "Ellen" (DeGeneres), Olson played a fictional science fair winner, lamenting in song that she was teased for being a nerd.
- The series Phineas and Ferb is the second time Olivia Olson and young British actor Thomas Sangster have been in a cast together. And in both Love Actually and in Phineas, Thomas plays a character who has a crush on Olivia.