Isabelle entered the acting profession when she was 7 years old. The Cartoon Network’s Casting director recognized her and gave her the opportunity to perform in one the shows named as Cartoon Fridays. However, in the year 2007, she got a wonderful opportunity to perform in the movie named as Hounddog. In the same year, she got another opportunity to play the major role in the movie titled Orphan along with the co-artists Peter Sarsgaard and Vera Farmiga. After the excessive search, she was finally selected to play the lead role in Warner Bros. Apart from the movies; she attracted the huge audiences through her role of a girl ghost in the television show named as Ghost Whisperer along with the co-star Jennifer Love Hewitt.
Additionally, she has also appeared in many of the commercials of the national brands such as pizza Hut as well as K-Mart. Most prominently, she has also performed in the popular comedy skit known as The Tonight Show with Jay Leno. Consequently, in the year 2011, she got a chance to play the role of Angie Vanderveer and the story of this movie was adapted from the novel written by Larry Beinhart. Apart from the acting profession, she was asked by the organization – Save the Kids in the year 2010 in order to serve as the celebrity advocate for their new project named as Caps for Good.