Lisa Robin Kelly, best known for portraying Topher Grace's sister (character Laurie Forman) on the sitcom 'That '70s Show,' has passed away at age 43.

TMZ is reporting that Kelly died in her sleep on Wednesday (Aug. 14) while attending a rehab facility in California.

She was brought in by her current boyfriend on Monday night but went into cardiac arrest a mere two days later.

Said a representative for Kelly, "She had been fighting demons for a while and finally lost her battle."

Unfortunately, the actress had been dealing with some problems lately, including four DUIs in the past three years as well as a divorce from her husband Robert Gilliam in July. Both parties had been accused of spousal abuse over the years, and TMZ reports that Gilliam was convicted of domestic battery against her just last month.

Kelly had been seeking to kick her drinking problem with rehab, but friends close to her say she went back to her old ways after a dispute with Gilliam.

May she now rest in peace.

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