By Associated Press PUBLISHED: 16:23 EST, 19 March 2013 | UPDATED: 10:48 EST, 20 March 2013 A mother of a teenage boy who was shot dead by his grandmother smiled as she left court on Tuesday after the 75-year-old was convicted of second-degree murder. Jennifer Hoffman described her mother Sandra Layne as a 'monster' outside the Michigan courtroom where she had been found guilty of killing 17-year-old Jonathan. Layne shot her grandson six times during an argument last spring as he pleaded with 911 responders to help him on the phone at the West Bloomfield Township home. Layne, a mother-of-five and retired schoolteacher, is expected to serve at least 14 years after a jury convicted her following two days of deliberations at the Pontiac court.
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Sandra Layne was convicted in Pontiac, Michigan for killing her 17-year-old grandson Jonathan Hoffman in May 2012
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The 75-year-old is expected to spent at least 14 years in jail
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Husband Fred Layne, 87, openly wept in court as his wife was shackled
Devastated: The husband of @placeholder, 87-year-old Fred Layne openly wept as the verdict was read on Tuesday