Lisa Robin Kelly's cause of death remains a mystery. The That 70's Show actress died in her sleep on Wednesday (14th August) whilst staying at an alcohol rehab centre in California. A post mortem was carried out on Saturday (17th August) with the hopes that her cause of death could be ruled. However a spokesperson for the L.A. Coroner's Office, speaking to TMZ, said the coroner is waiting for the results of a toxicology report. This could take a number of weeks, according to the spokesperson.

Lisa Robin Kelly
Lisa Robin Kelly photographed in 1999 whilst appearing on That 70's Show.

Kelly died whilst staying at an alcohol rehab centre. She checked in last Monday (12th) after her boyfriend rushed her to hospital on Sunday. TMZ reports that her blood alcohol level, when checked in hospital, was at 0.34. 

Her representative, Craig Wykoff, released a statement shortly after his client's death. He announced her death and said "she had been fighting demons for a while and finally lost her battle."

Mila Kunis and Ashton Kutcher
Mila Kunis and Ashton Kutcher watching a basketball game in L.A.

Sadly, Kelly was attempting to overcome her alcohol addiction when she died. Wykoff said he had spoken to her on Monday and she was "hopeful and confident, looking forward to putting this part of her life behind her."

Kelly was best known for her role in That 70's Show, which aired on Fox between 1998 and 2006. Kelly played Laurie, the elder sister of Eric Forman (Topher Grace). Alongside Grace, Kelly's co-stars included Mila Kunis, Ashton Kutcher and Laura Prepon

Contactmusic sends their condolences to Lisa Robin Kelly's family, friends and co-workers at this difficult time. 

Lisa Robin Kelly
Lisa Robin Kelly photographed in 1999.