Lisa Robin Kelly | ' '70s Show' actress, 43

Lisa Robin Kelly, 43, who played the promiscuous older sister on the Fox sitcom That '70s Show, has died.

Ms. Kelly's agent, Craig Wyckoff, confirmed her death, saying that the actress had been dealing with troubles with addiction at the time of her death and had voluntarily checked into a California rehab facility Monday. She apparently died in her sleep Wednesday night.

"I spoke to her on Monday and she was hopeful and confident, looking forward to putting this part of her life behind her," Wyckoff said in a statement. "Last night she lost the battle. Cause of death has not been issued yet and no death certificate has been issued."

Her acting career never reached the heights of her costars Ashton Kutcher and Mila Kunis. In recent years, she had several run-ins with law enforcement, most recently an arrest in June on suspicion of drunken driving after her car stalled on the freeway in Burbank, Calif.

Ms. Kelly said her drinking problems began in 2003, after a miscarriage. The drinking eventually led to her departure from the series.

She told ABC News in 2012: "I had lost a baby. As a result of that, I lost everything and I was abusing alcohol." - L.A. Times