NEW : Lawyer of Austrian incest claims that his client has a mental illness . Copyright 2008 CNN . Fritzl imprisoned and raped daughter , also fathered her children , witnesses say . Wife of Josef , was too scared to question him , her sister says . Fritzl 's wife insisted on keeping family healthy , according to her sister .
NEW : Lawyer of Austrian incest claims that his client has a mental illness . Fritzl imprisoned and raped daughter , also fathered her children , witnesses say . Wife of Josef , was too scared to question him , her sister says . Fritzl 's wife insisted on keeping family healthy , according to her sister .