Lisa Robin Kelly cause of death: Accidental overdose
Although she was in an alcohol rehabilitation facility at the time of her death, TMZ.com reports that unidentified drugs were found in Kelly's system. The treatment at the facility began when the actress tested for a potentially fatal blood-alcohol level. More information on the specific drugs may be available when the Coroner releases the full report in a couple of weeks.
Best known for playing Laurie, the older sister of main character Eric Forman on "That '70s Show," Kelly had a history of addiction prior to her death.