Phyllis was born deaf. In 1949, at age 5, her parents enrolled Phyllis in the same school they both had attended, ND School for the Deaf.

Frelich was born to deaf parents Esther (née Dockter) and Philip Frelich. She was one of nine siblings. Her parents were alumni of the North Dakota School for the Deaf. At Gallaudet she completed a degree in library science, but also participated in theater.

Actress. She won a Tony Award for "Children of a Lesser God". From 1981 to 2011, she appeared in several films and television shows including, "Barney Miller: Stormy Weather", "More Than Friends", "Love is Never Silent", "ER: Stuck on You", "ER: Nobody Doesn't Like Amanda Lee", "Children on Their Birthdays", "CSI: Crime Scene Investigation", "The Two Mrs. Grissom's". Frelich died at the age of seventy because of a rare degenerative neurological disease.