Marilyn Monroe's biggest secret was her mother's battle with mental illness.
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A new TV movie reveals that Marilyn lived in fear of inheriting her mother's madness.
INSIDE EDITION went behind the scenes of the set of The Secret Life of Marilyn Monroe, which will air on the Lifetime Network. Kelli Garner plays Marilyn and Susan Sarandon plays Marilyn's mom, Gladys Monroe Baker.
Garner practically stayed in character when we spoke to her.
Playing the iconic movie goddess is not something the actress takes lightly. She said, "It's daunting you're playing a human being and I don't want to mimic or imitate her."
The truth is that doctors diagnosed Marilyn's mother with Paranoid Schizophrenia. Gladys Baker's own mother committed suicide, so mental illness haunted the family.
As a child, Marilyn even lived in foster homes and an orphanage while her mother was institutionalized.
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The movie depicts the day Marilyn brought her great love Joe DiMaggio to meet her then institutionalized mom.
Marilyn is said to have spent time in an institution, as seen in this scene from the movie. One archival video shows the real Marilyn leaving a hospital in 1954.
Garner said, "At the time in which she lived metal health was so taboo."
Her mother died in 1984, outliving her daughter by 22 years but never understanding the indelible mark that her little girl had left on the world.
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