Ariel Waller (born May 16, 1998) is a retired Canadian actress. She was one of the protagonists of the series Life with Derek, playing the role of Marti Venturi in the sitcom. She had a major role in the film Cinderella Man, and also appeared in Kardia as the young Hope. She was nominated for the Young Artist Award in both 2007 and 2008. (Via Wikipedia)