Kelsey Deanne was born on April 21 in Fort Worth, Texas, to Mike Grubbs, a technology executive, and Rebecca Grubbs, an artist. She has one older brother, David, an entrepreneur. Kelsey is a classically trained concert pianist. Growing up she danced ballet, tap and modern, was in cheer leading, symphonic and marching band (five instruments), symphony (viola), competitive road cycling (California State Champ 2002), scuba diving internationally, and collegiate cross-country and track. She studied at The Royal Academy of Dramatic Art in London, as well as in New York City with professors at Tisch-NYU, The American Academy of Dramatic Art, New York Film Academy, and Harry O'Reilly, a protege of Geraldine Page and Uta Hagen. She studies in Los Angeles at the Beverly Hills Playhouse with Howie Deutch, and in London privately with Brigid Panet (RADA). She graduated from Burlingame High School one year early to attend Lawrence University Conservatory of Music in Appleton, WI on a piano performance scholarship. She was on the Cross-Country and Track teams and earned a B.A. in three years. Kelsey continued her education to complete two M.A. degrees, from University of North Texas and The New School, New York, respectively.