LOS ANGELES (Reuters) - Actress Lisa Robin Kelly, best known for her supporting role on the popular Fox television comedy "That '70s Show," has died at age 43, days after checking into a treatment facility for substance abuse, her agent said on Thursday.
The blonde actress co-starred in about 50 episodes of the series, which ran from 1998 to 2003, as the attractive, promiscuous Laurie Forman, the older, college-age sister of the lead character, Eric Forman, played by Topher Grace.
Kelly left the series in the sixth season, replaced by actress Christina Moore.
According to her agent, Craig Wyckoff, Kelly died on Wednesday evening at the facility.
"Lisa had voluntarily checked herself into a treatment facility early this week where she was battling the addiction problems that have plagued her these past few years," he said.
"I spoke to her on Monday, and she was hopeful and confident, looking forward to putting this part of her life behind her. Last night, she lost the battle," he added.
He gave no further details and said a cause of death has yet to be determined.
Kelly had appeared in number television shows before landing her role on "That '70s Show" but earned few screen credits after leaving the series.
The series, set in the 1970s disco era, centered on the mishaps and high-jinks of a group of teenage friends in Wisconsin, with much of the action set in the basement of the Foreman home, where the characters often gathered.
The member of the cast who went on to the greatest success after the show was Ashton Kutcher, who co-starred as Eric's hunky friend Kelso, who was known to cheat on his girlfriend with Laurie.
Reporting by Piya Sinha-Roy; Writing by Steve Gorman; Editing by Cynthia Johnston