Allen made her motion picture debut in Enough starring as Gracie, the young daughter of Jennifer Lopez's character. Before Enough, Allen appeared in many commercials, the first of which when she was only four months old in a Maytag commercial. Following this, Allen appeared in many commercials including the very popular McDonald's Happy MealThe Tigger Movie promotion which ran for three weeks, the longest McDonald's promotion of its time. After she filmed Enough, Allen was picked up almost right away by NBC to play Hannah Hansen on its Friday night family drama Providence from 2001 until the show was discontinued in December 2002. She was the third Hannah Hansen and the first non-twin role. Providence co-stars Melina Kanakaredes and Seth Peterson have said that it was easy to be upstaged by Allen with her wacky outfits, her perfect timing and her cuteness because the camera loved her. After Providence ended, Allen shot many commercials including a Jif Peanut Butter commercial called "Sleepover" which has been reported to be seen on air until late 2005, early 2006. Allen was next seen on a TV show as a guest star on 's 2002-2003 season 1 finale playing Emma Kaye, a little girl who was abducted by a child molester. The episode aired in May 2003. Allen continued to film many commercials and then in February 2004, she landed a small part on General Hospital playing Molly Farrell, a young girl trapped with her young brother in a hotel fire. After this short stint, Allen was asked to return to the show to play Luke and Laura Spencer's daughter Lesley Lu Spencer, a change that required that the character's age be retroactively lowered. Allen appeared as Lulu every now and then, often with TV grandmother Lesley. Allen left General Hospital when Julie Marie Berman took over the role in fall 2005 to play a SORASed Lulu. During her time on General Hospital, Allen filmed a short film called Walls of Jericho for the 168 Film Festival. Here she was reunited with on-screen mom Karen Geraghty who had also played Allen's mother in her 2003 Jif commercial. Karen stated after filming Walls of Jericho that "I have worked with many kids before through commercials, short films, etc. but none compare to Tessa. I love working with her and would do so again in a heartbeat". For her role as Emily in this short film, Allen was nominated for best supporting actress. After Allen's run as Lulu Spencer ended, she continued to film TV commercials including a Mass Mutual commercial which aired during both the 2006 and 2007 US Tennis Open. In 2006, Allen was in her first theatre production as the evil stepsister Anastasia in Cinderella and in early 2007, Allen shot another short film, this time a USC grad film entitled Open House, where she plays a younger version of the main character. In March 2007, Allen shot a Doritos commercial which featured the music groupThe Black Eyed Peas. In October 2007, Allen began filming another USC grad film called Sunnier Days, where she plays the lead character on a road trip with her falling-apart family. Sunnier Days won awards at the UCLA Directors Spotlight. In May 2008, Allen booked and shot another lead role in a student film called The Moment She Fell, a story about a father and daughter learning to deal with the grief of their wife/mother as well as their new life together. Allen was born in Manhattan Beach, California. She has three sisters, Madison, Jeanne, and Adeline, all of whom have acted in the past.
