" Kehoe slashed boys ' throats , left them for dead , tried to kill herself , prosecutor says . A mother 's plot to blame a stranger for killing her sons went awry when one of the boys survived and told police how Michelle Kehoe cut his throat , then moved on to his younger brother , an Iowa prosecutor said Thursday . Iowa jury hears tape of surviving boy telling police his mother cut him , hurt brother . Police say she hatched plan years before to blame attacks on stranger . Kehoe 's lawyers have filed a plea of intent to present an insanity defense .
" Kehoe slashed boys ' throats , left them for dead , tried to kill herself , prosecutor says . Iowa jury hears tape of surviving boy telling police his mother cut him , hurt brother . Police say she hatched plan years before to blame attacks on stranger . Kehoe 's lawyers have filed a plea of intent to present an insanity defense .