Spending her early years in Virginia, Graham attended North Springfield Elementary School in Springfield, Virginia. Her family then moved to the Conejo Valley, Los Angeles, California, where she attended Sumac Elementary School, Lindero Canyon Middle School, and Agoura High School where she graduated in 1988. Initially, Heather's parents were supportive of her budding acting career. However, her parents were concerned that she should not appear in any movie featuring sex or nudity. Breaking away from that mold, Heather appeared fully nude in several scenes in her breakout role in Boogie Nights. Heather is currently estranged from her parents, who are still devout Catholics