'Superman' actress Margot Kidder dies at 69

Margot Kidder, who famously played Lois Lane opposite Christopher Reeve in 1978's "Superman," died on Sunday at the age of 69.

The actress passed away at her home in Montana, a spokesperson at Franzen-Davis funeral home in Livingston, Montana, confirmed to TMZ on Monday. Her cause of death is unknown at this point.

Kidder went on to portray her iconic character in the film's three sequels "Superman II," "Superman III" and "Superman IV: The Quest for Peace" and continued acting in the decades since her breakout role.

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The Canadian actress also appeared in "The Amityville Horror," "Black Christmas" and TV series "Boston Common." She won an Emmy for her performance on children's show "R.L. Stine's The Haunting Hour" and appeared in the Broadway production of "The Vagina Monologues" in 2002.

See photos of Margot Kidder:

Kidder suffered a widely-publicized manic breakdown in April of 1996, which led to her being diagnosed with bipolar disorder. After a computer virus caused her to permanently lose years worth of drafts of her autobiography, Kidder disappeared for days before being found in a distressed state after reportedly being raped. She was placed in psychiatric care and later said in 2007 that she hadn't had a serious manic episode in over a decade.

As TMZ notes, she also became an outspoken advocate for mental health in the later part of her life.

The actress was married and divorced three times and shared her only daughter, Maggie McGaune, with first husband, novelist Thomas McGuane. She was also romantically connected with Steven Spielberg, former Canadian prime minister Pierre Trudeau (father to current PM Justin Trudeau) and Richard Pryor.

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