Smith dropped out of high school at age 14 in 1982, married in 1985, and divorced in 1993. In 1994, her highly publicized second marriage to 89-year old billionaire J. Howard Marshall resulted in speculation that she married the octogenarian for his money, which she denied. Following Marshall's death in 1995, Smith began a lengthy legal battle over a share of his estate. Her cases reached the Supreme Court of the United States: Marshall v. Marshall on a question of federal jurisdiction and Stern v. Marshall on a question of bankruptcy court authority.
Smith died in 2007 in a Hollywood, Florida hotel room as a result of an overdose of prescription drugs. In the months leading up to her death, Smith was the focus of renewed press coverage surrounding the death of her son, Daniel, and the paternity and custody battle over her newborn daughter, Dannielynn Birkhead.