Her publicist, Jeffrey Lane, who made the announcement, said Frann died in her sleep and was discovered by her longtime boyfriend, Jonathan Cookson. Although no official cause of death has yet been determined, Lane speculated that the actress died of heart failure.
Although she was a familiar face on the tube in the '70s and '80s, regularly appearing in soaps like Return to Peyton Place and Days of Our Lives and popping up in bit parts on The Mary Tyler Moore Show, Hawaii Five-O, The Rockford Files and WKRP in Cincinnati, Frann will always be remembered as Newhart's Joanna Louden, the sweet, grounded matriarch who oversaw a hotel full of oddballs. The sitcom ran on CBS from 1982-1990.
In a statement, Bob Newhart remembered his TV wife as a consummate professional. "There is shock and terrible sadness at CBS over the death of Mary Frann," the network said in its press release. "She was always a joy to work with."
Born Mary Luecke in St. Louis, she began her show-biz career early, as a child model, eventually making the finals of the Junior Miss Pageant. She later took to the stage as a member of St. Louis' Gateway Repertory Theater. Frann also had stints as a TV reporter for the NBC affiliate in St. Louis and the ABC affiliate in Chicago.
She is survived by two sisters, Pat and Jackie, and a brother, Harry.