Arleen Sorkin, the actor who first voiced Batman mainstay Harley Quinn, passed away at 67 years old.

Reports of her passing went around on social media following a tweet from voice actor Neil Kaplan, and were later corroborated by the Hollywood Reporter. Sources speaking to the outlet reveal she’d passed on Thursday, August 24, and that she’d been unable to act in recent years due to health issues.

Born October 14, 1955, Sorkin came into prominence during the 80s as Calliope Jones in Days of Our Lives. Paul Dini, a key creative on Batman: The Animated Series, was a friend of hers in college and based the character of Harley on Sorkin, saying he was inspired by a Days episode where she played a jester in a dream sequence. Aspects of Sorkin’s life—such as her Brooklyn accent and being Jewish—were incorporated into Harley, who was intended to be a one-and-done character in the 1992 episode “Joker’s Favor.” But the reaction to Sorkin’s performance was so strong that Harley became a recurring character on the show and she was eventually incorporated into the DC Comics canon.

Harley would go to have a life of her own and appear regularly throughout other DC media, both connected to B:TAS (such as Batman Beyond: Return of the Joker) and not. Sorkin voiced Harley in a handful of video games, with her final roles being 2009’s Batman: Arkham Asylum and 2011’s DC Universe Online. Since Batman: Arkham City in 2011, Harley has regularly been voiced by Tara Strong in animation and video games, while Margot Robbie has played the character in live-action.

Sorkin is survived by her husband Christopher Lloyd and their sons Eli and Owen, and our thoughts go out to them at this time.

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