The seven-member jury recommended no criminal charges.
The jury deliberated less than two hours before returning the verdict Monday. The inquest began in November to determine what killed 20-year-old Daniel Smith.
The son of the former Playboy playmate died in September 2006 after coming to the Bahamas to meet his new baby sister. His mother died early the next year.
An autopsy found that Daniel likely died from a combination of drugs, including methadone and antidepressants.
