Barzee was married twice. The first violent marriage in 1964 produced six children in 10 years. She was medicated for depression and wild, manipulative mood swings, the Deseret News reported.
She had a nervous breakdown before she left the marriage in 1983, the Salt Lake Tribune reported Monday.
Some of Barzee's children claim emotional and physical abuse.
"She was definitely my 'Mommie Dearest' back in the day," youngest daughter LouRee Gayler said, referring to Christina Crawford's memoir in which she alleged her adoptive mother, the actress Joan Crawford, was abusive. "My mother was sick for a long time."
Barzee met Brian David Mitchell in a therapy group and married him in 1985. She went off her medication and began a spiral downward, Barzee's mother, Dora Corbett said, that culminated in Barzee, 64, pleading guilty in federal court to the 2002 kidnapping of Smart, then 14, the Deseret News said.
She was sentenced to 15 years in prison with six years credit for time served at Utah State Mental Hospital. A competency hearing to determine if Mitchell will stand trial for the kidnapping began Monday.
"Now that I see that she's competent and has her mind back, I am so happy for her," Corbett, 88, said. "I feel a lot better about it all. She is willing to spend the rest of her life in prison for what she's done."