A mother from Chicago has been charged with first-degree murder for allegedly stabbing her 5-year-old daughter to death.

Simone Austin, 27, allegedly stabbed Serenity Arrington in the throat in front of the girl’s older sister using a serrated knife on Saturday morning.

According to the prosecutors, Austin asked the older girl to leave the room, but peeked through a hole in the doorknob and watched her mother pull the knife out from under a pillow and cut Serenity’s neck.

The girl screamed, as she saw Austin stabbing Serenity, and she tried to pull her mother away from her sister by the hair.

Their grandfather, who also lives in the same apartment and went out to get coffee at that time, came back to find the front door locked.

He went around and entered through the kitchen door, where he saw Austin undressing and immediately went out to the porch as the older sister ran outside and yelled that her mom had just killed her sister.

Austin then brought Serenity outside and laid her down on the grass, and as the neighbors saw the child bleeding from the gash in her throat, they heard the mother apologizing.

The child was rushed to Stroger Hospital, where she was pronounced dead from multiple stab wounds.

An autopsy confirms the cause of death as homicide, and one of the wounds to her throat went almost completely through the back of the neck.

“We’ve had previous calls there for domestic violence where the mother was the victim of domestic violence and other people in the family called,”said Chicago Police Supt. David Brown.

Officials say Austin does not have a prior criminal background, and had no indication that she has ever harmed her children before.

It is still unclear as to what lead Austin to stab her own child, but detectives say they are investigating on the possibility that she may have a history of mental illness.