In what was described as a psychotic episode, a DeKalb County teenager stabbed her 2-year-old sister again and again until the little girl died. Then she tried to cover up what she’d done, prosecutors said.

Monday afternoon, Ty’Aisa Jackson, 14, was sentenced to 12 years, eight of which must be served behind bars, after pleading guilty to involuntary manslaughter. If she had been convicted of a murder charge, she could have faced life in prison.

But the sentencing was no happy ending for anyone, the DeKalb District Attorney’s Office said.

“It’s really tragic. I can’t imagine what this mother is going through,” Nicole Golden, chief assistant district attorney, said outside of the courthouse. “She’s losing two daughters, in essence.”

Ty’Aisa will get credit for the time she’s already spent in jail. She’ll remain at a Regional Youth Detention Center until she turns 17 and is moved to an adult correctional facility, the DA said.

In September, through her attorneys, Ty’Aisa rejected a plea deal that would have sentenced her to 20 years, including 10 in prison. Her attorneys had argued for her to serve five years in prison. But Monday, her defense team agreed in Judge Gregory Adams’ courtroom to revised terms.

Ty’Aisa was 13 when she was arrested and accused of fatally stabbing her 2-year-old sister Sasha LaMaya Ray.

On Nov. 19, 2012, she was watching her younger siblings at their home near Decatur when her parents were called and told that young Sasha was missing.

Ty’Aisa said she couldn’t find the toddler and joined in the search after changing her own bloody clothes, according to police.

Sasha was found in the backyard of the townhome with multiple stab wounds, police said, and died as her parents rushed her to the hospital in their car. Ty’Aisa was taken in later the same day for questioning.

Later she called Shelton Ray, her stepfather, from police headquarters to confess that she had stabbed her sister, Ray told The Atlanta Journal-Constitution at the time.

After the sentencing Monday, Ray told Channel 2 Action News he hoped the teen could stay positive and focused on the future.

“We still love Ty’Aisa,” he said.