Her television roles include Another World from 1989 to 1992; Cobra from 1993 to 1994; Profit in 1996; Hope Island in 1999; and Stephen King's Kingdom Hospital in 2004. She starred in the Canadian TV series, Falcon Beach in 2006. Hossack has made guest appearances on television shows such as Sliders, Mysterious Ways, Da Vinci's Inquest, The Outer Limits, Eureka,Stargate SG-1, Stargate: Atlantis, and Fringe. She played Mrs. Oliver on the TV series Reaper. She also played Deanna Campbell, the mother of Mary Winchester and the maternal grandmother of Dean Winchester and Sam Winchester on the CW paranormal/horror series Supernatural. Also a singer, Hossack resides in Toronto.