A Maricopa County Superior Court spokeswoman says Judge Pamela Svoboda also sentenced 27-year-old Franchesca Lourdes Ann Castro on Friday to three months of deferred jail time and lifetime supervised probation.
Castro and the son's stepfather, Jay Philip Cason, were arrested in March 2014 after firefighters responded to a report of a boy with severe injuries to his back.
According to police, Castro and Cason became upset and struck the child after he returned home from daycare with the empty chip bag in his jacket pocket.
Cason pleaded guilty on April 23 to child abuse. He awaits sentencing.
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