SOLON TOWNSHIP, Mich. -  The sheriff's office officially ruled the deaths of a mom and her three young daughters a murder-suicide after autopsies were completed Wednesday. 

Kent County Sheriff Michelle LaJoye-Young said 28-year-old Aubrianne Moore shot and killed her three daughters before driving to the home where she lived with her boyfriend on 19 Mile Road NE, and shooting herself. 

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According to the sheriff's office, Moore used a bolt-action hunting style rifle.

"We can be quite certain that Mom committed the homicides," said LaJoye-Young. "There were three shots that killed the children and then one shot that was the self inflicted gunshot wound with Mom."

Moore's boyfriend, who is also the father of her youngest daughter, was asleep inside at the time of the shooting. 

"He woke up sometime after and discovered the bodies in the yard," said LaJoye-Young. 

Deputies identified the three daughters as 2-year-old Alaina Rau, 6-year-old Cassidy Rodery and 8-year-old Kyrie Rodery.

Sheriff LaJoye-Young says they have not found a suicide note or other clues that explain the mother's motive. Court documents show that Moore struggled with mental illness. Last September, a social worker diagnosed the mother with unspecified schizophrenia and said she was a danger to herself. 

"We are just getting to that part of the investigation," LaJoye-Young said.

"It appears Mom had a substantial mental health issue she was struggling with and that likely led to the homicide."

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