URBANA, Ohio (AP) — A teenage boy in Ohio who claimed a second personality fatally shot and stabbed his father's girlfriend has been sentenced to at least 28 years in prison.

Sixteen-year-old Donovan Nicholas was sentenced Tuesday in Champaign County to life in prison with no chance for parole for 25 years. He also received a mandatory three years because a gun was used.

Nicholas was convicted earlier of aggravated murder in 40-year-old Heidi Fay Taylor's April 2017 slaying. She was stabbed more than 60 times.

Nicholas was 14 when he told a 911 dispatcher an alternate personality killed his mother. He denied killing Taylor and blamed the slaying on someone named Jeff.

Defense attorney Darrell Heckman has said he'll appeal the conviction and the case should have remained in juvenile court.