Olivia Olson

Olivia Olson is an actress, singer, and voice artist best known for her work spanning both animation and on-camera roles. Olson voiced Marceline the Vampire Queen in the Cartoon Network series Adventure Time (2010–2018). She provided the singing voice and speaking voice for the iconic character.

She is the voice of Vanessa Doofenshmirtz in the Phineas and Ferb franchise and Milo Murphy's Law, Adventure Time: Fionna and Cake, and several video games.

Olivia portrayed Joanna in the holiday classic Love Actually (2003), where she starred alongside Hugh Grant and Liam Neeson as the object of young Sam’s affection. She reprised her role in the 2017 short sequel Red Nose Day Actually.