Everyone is familiar with DC's "Superman" comics and films. Although there has been multiple spin-offs and lots of changes with the newer comics and movies such as with the movies "Man of Steel," "Superman" helped shape the comic industry as we know it today. On Sunday, May 13, people across the globe mourned the passing of a DC Universe star, Margot Kidder.

A very influential person in the Superman universe [VIDEO], Kidder, passed away Sunday at her home in Montana, the cause of death is still listed as unknown as of right now.

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911 received a call saying that she was unconscious and not breathing right before she passed but according to Bruce Becker, the Park County Attorney, the passing is not being looked at as foul play.

Kidder had been reportedly ill with flu days before passing and had called in sick to the "Drew and Mike Show" on May 9. It is still unclear if this was related to her death, but could have played a factor.

Kidder filmography

Margot Kidder starred in three different Superman films as the original Lois Lane with Christopher Reeve. She got her start in acting in the 1960s but didn't receive proper notoriety until she took the role of Lois Lane. Margot Kidder also starred in other movies throughout her acting career such as Rob Zombie's 2009 remake spin-off of "Halloween II" and "The Amityville Horror," in which she had played Kathy Lutz. She also dated notable stars like Steven Spielberg. Her last movie was "The Neighborhood," and she had recently been awarded for her role in R. L. Stine’s children show "The Haunting Hour." She had one child named Maggie with American writer Thomas McGuane whom she had briefly married in 1975 and later divorced in 1977.

Kidder: mental health advocate

According to DailyMail, Margot Kidder [VIDEO] was diagnosed with Bipolar Disorder early in life and was very open about her struggle which left her homeless in 1996. She was later checked into a psychiatric facility after ending up in a stranger's backyard and fortunately was able to get help for her mania and other mental health problems. She struggled for years with Bipolar Disorder and became a major advocate for mental health awareness, hoping that her story and experiences could help others with their ongoing mental health problems as well. Margot Kidder is survived by her daughter Maggie McGuane, 45, and grandchildren Charlie Kim and Mazie Kim. Her funeral date is still-to-be-announced.