The daughter of Johnny Cash believes her mother was wrongly portrayed as a "mad little psycho" in a movie about the singer's life, Walk the Line.
Cash died four months after the death of his second wife
Kathy Cash was so upset at the portrayal of Vivian Liberto Distin, Cash's first wife, that she walked out of a screening given to the family.
But she praised the performances of Joaquin Phoenix as Cash and Reese Witherspoon as June Carter Cash.
Johnny Cash died in September 2003 at the age of 71.
Kathy Cash said the film's depiction of her mother, who died earlier this year, was "not true".
"My mom was basically a nonentity in the entire film except for the mad little psycho who hated his career," she said.
"She loved his career and was proud of him until he started taking drugs and stopped coming home."
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Kathy Cash also complained that the film failed to show the singer's children and their suffering during their father's fight with drugs and their parents' divorce.
The daughter said she expected "dyed-in-the-wool fans" to object to the film.
John Carter Cash, the singer's only child from his second marriage and the film's executive producer, admitted his half-sister's criticisms had merit.
"I'm compassionately understanding," he said. "The point of the film is my parents' love affair."
First wife Ms Distin and Cash were married for 13 years and had four children together.
The singer pledged to remain faithful to Ms Distin in his song I Walk the Line, which inspired the film's title.