Stephanie Lynne Niznik (May 20, 1967 – June 23, 2019) was an American film, television, and theatre actress, most famous for her role as Nina Feeney on Everwood.
Niznik attended the California Institute of the Arts. Besides Everwood, Niznik's television roles include guest roles on Dr. Quinn, Medicine Woman, Profiler, Sliders, JAG, Frasier, Epoch, Star Trek: Enterprise, Traveler, and Diagnosis: Murder, in addition to being a series regular on the mid-1990s action drama Vanishing Son and the 2007 drama Life Is Wild. She has also appeared in the films Star Trek: Insurrection and Exit to Eden.
She died in Encino, California on June 23, 2019 at the age of 52. According to the L.A. Coroner, Stephanie Niznik died from Chronic Liver Disease, Chronic Alcohol Use (Manner of Death: Natural).