Criminal charges have been filed against a mother accused in the death of her four-year-old son -- her only child, who had autism.

The accused is 23-year-old Amelia Di Stasio, who faces a charge of first degree intentional homicide in the death of Antonio Di Stasio, which happened on September 28th near 17th and Grant.

Di Stasio faces life in prison if convicted.

According to a criminal complaint, around 7:30 a.m. on September 28th, the Milwaukee Fire Department was dispatched to the home at 17th and Grant for a report of "smoke." Smoke was observed coming from Apartment #2 and firefighters forced entry into the home. Smoke was observed coming from the stove, and a pile of clothing in the bathroom (in the bathtub) was noted to be smoking.

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Firefighters found a lifeless child with his hands bound behind his back with several belts. The complaint says there was a garbage bag over his head. "The majority of his body was burned," the complaint says. Investigators learned the victim's body had been set on fire with the use of an unknown accelerant. A pet guinea pig was found drowned in its cage next to the tub, the complaint says. A bottle of canola cooking oil was located on the bathroom sink.

Police soon arrived, and learned the victim was four-year-old Antonio Di Stasio, who lived in the apartment with his mother, Amelia. She was not home when first responders arrived.

The complaint indicates the apartment's smoke detector had been removed and placed in water.

Investigators spoke with a witness, who lived in the apartment building at 17th and Grant. She said Amelia and Antonio had moved in two months prior, and said Amelia "wasn't friendly and kept to herself." She noted that on September 27th, one day before Antonio died, she heard Antonio say "Please, Mommy. Stop! I won't do it again." She said she heard Amelia yell "Shut up." On the morning Antonio died, she said she heard "a banging noise" coming from Amelia's apartment unit.

An autopsy revealed seven belts were used to secure Antonio Di Stasio's hands and arms to his sides, and a plastic bag had been placed over his head -- pulled tight and knotted at the back of his head. The autopsy revealed "significant charring" to his skin, and thermal injuries "to the majority of his body." His death was ruled a homicide.

A second witness told investigators she saw a woman jump from the windowsill of the apartment building on September 28th. She noted that the woman looked "frazzled," according to the complaint.

Amelia Di Stasio was arrested later on September 28th after an officer spotted her walking along W. Wisconsin Avenue.

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