Actress Katherine Cannon broke into the television business with a succession of guest roles on various shows throughout the 1970s. In addition to appearing on such widely remembered series as "Gunsmoke" and "Ironside," she carved out a niche with an array of doctor dramas that included "Emergency!," "Medical Center," and the feature-film exploitation thriller "Private Duty Nurses." As the 1980s drew closer, Cannon frequented such other high-profile series as "ChiPs," "Hawaii Five-O," and "The Incredible Hulk" before settling down with a number of "Little House on the Prairie" alumni as a regular on the Michael-Landon-created frontier Western "Father Murphy." For two seasons, the actress portrayed orphan-rearing schoolmarm Mae Woodward, an image she would completely reverse nearly a decade later with her scenery-chewing recurring role as Donna Martin's bigoted and arrogant mother on the 1990-2000 teen soap "Beverly Hills, 90210." Cannon has made occasional film appearances in such projects as the rip-roaring alien-possession movie "The Hidden" (1987) and the limited-release action-thriller "Shattered Lies" (2002).