Glynnis Mary O'Connor was born on November 19, 1955, in Long Island. Her father, Daniel O'Connor, was a producer, executive producer, and managing director of NBC Special News for over 25 years. Her mother, Lenka Peterson, was a stage, film, and TV actress who worked with Glynnis in a couple of her assignments. Glynnis's brother, Darren O'Connor, was also an actor in the 1970s.
In her late teens, Glynnis was featured on the daytime soap As the World Turns and the prime-time family series Sons and Daughters opposite Gary Frank. She graduated from the State University of New York and found her niche portraying sensitive, fretful young romantics in the 1970s. She hit her stride early with Jeremy, Ode to Billy Joe, and Our Town opposite Robby Benson.
Glynnis's other prime 1970s credits included All Together Now, The Boy in the Plastic Bubble, and Baby Blue Marine opposite John Travolta. She also played a sensitive misfit in California Dreaming, a dancer in Those Lips, Those Eyes, and ill-fated tennis champion Maureen Connolly in Little Mo.
Despite her continued excellence, Glynnis surprisingly did not hit the top ranks. She continued to work in film and television, appearing in Melanie, Why Me?, Love Leads the Way: A True Story, Johnny Dangerously, New Best Friend, Graduation, Heaven's Messenger, The Trouble with Cali, The Historian, Angelica, and Diane.
Glynnis has also made appearances on TV, including guest parts on "The Chisholms," "The New Twilight Zone," "Reasonable Doubts," and "Young Americans," as well as recurring parts on Law & Order and Condor. She has also appeared in a number of TV movies, including Sins of the Father, Too Good to Be True, Nightmare in the Daylight, Death in Small Doses, and Ellen Foster.
Glynnis is married to Douglas Stern and they have two daughters, Lindsay and Hana.