The UP cable channel said Valerie Harper is filming a TV movie in Canada, just five months after the actress revealed she had been diagnosed with cancer.
Harper gained fame playing Rhoda Morgenstern on television's The Mary Tyler Moore Show and Rhoda.
In March, the 73-year-old actress said she's been diagnosed with a rare, incurable brain cancer but that she intended to live each moment fully.
The movie, being shot in Vancouver, is titled The Town that Came A-Courtin', is based on a novel by Ronda Rich and also stars Lauren Holly, Cameron Bancroft and Lucie Guest.
UP, which described the movie as an uplifting romance, said Wednesday it welcomed the "inspirational" Harper as part of the project.
UP's The Town that Came A-Courtin" will air in January 2014, the channel said.