The actors met with fans, shared memories from the show and introduced clips from the sitcom.
Williams, now 58, said he has few memories of being on the show and relies on fans' stories to recall the experience, according to the Enquirer. He also performed a parody of Eminem's "The Real Slim Shady" called "The Real Greg Brady." (Wince.)
The original Kings Island episode aired during the show's fifth and final season, when patriarch Mike Brady (Robert Reed) had drawn up architectural plans to expand the park.
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