Actress Stephanie Niznit has died at the age of 52.

The actress, who was known for her work as Perim in Star Trek: Insurrection and as Nina Feeney in Everwood, passed away unexpectedly in Encino, Calif. on June 23. Her cause of death has not yet been revealed.

Niznik, a native of Bangor, Maine, also starred in the mystery-action series Vanishing Son and had recurring roles in Diagnosis Murder as well as a regular role in the short-lived family adventure drama series Life Is Wild. She also appeared in guest roles in some of TV's most popular dramas including Grey's Anatomy, CSI: Miami, and Lost.

Scott Wolf, who appeared as her on-screen love interest in Everwood, wrote of the news, "This is heartbreaking. She was so kind, and so fun to work with. I'm lucky to have known her. Rest In Peace Stephanie."

Everwood's creator and showrunner, Greg Berlanti and Rita Mimoun, also issued a statement in the wake of the news, writing, "Everwood was more than just a television show. It was a family. We recently lost the mother of our tribe, Stephanie Niznik. Stephanie played Nina, the next door neighbor to Andy Brown, and the woman who helped raise his children as he struggled with being a single father. She continued that role off-screen by being an incredible friend, a nurturing mother figure to our younger cast members and an artist who brought warmth, compassion, and humor to every episode and our set. Everyone who was lucky to know and work with her will miss her dearly."

Sarah Drew, who also starred in the series, echoed that sentiment by writing, "We grew to be a tight knit community during our time on Everwood. Stephanie was a loving, open hearted friend and a bright light on set. I can't believe she is gone."

Throughout the weekend, Niznik's friends and fans continued to offer words of tribute to the late actress.