Three-year-old Devin Drake was admitted to Mercy Hospital in Coon Rapids on August 30 for injuries inflicted by his mother's boyfriend, StarTribune said. Hennepin country medical center staff said this was one of the worst abuse cases they have seen, Pioneer Press reports. Drake's mother's boyfriend was sentenced to more than 15 years in prison last August after pleading guilty on accounts of second-degree murder, StarTribune said. Drake died at Hennepin county medical center on Sept. 3 after suffering from a right cerebral hemorrhage, two collapsed lungs and retinal hemorrhaging, StarTribune reports. Drake's mother, 41-year-old Elizabeth Ann Moorman, neglected to take her son to the hospital until the following evening after the injuries her boyfriend inflicted on Drake because she had warrants out for her arrest, Pioneer Press said. Both Moorman and her boyfriend struggled with struggled with addictions to pain medication, Pioneer Press said. Moorman pleaded guilty on accounts of second-degree manslaughter and neglect of a child and was sentenced Thursday to four years in prison, StarTribune said.