(WHDH) — An Atlanta woman has pleaded guilty to murder in the death of a 3-year-old boy who she beat to death with a baseball bat for eating a cupcake.

LaShirley Morris was sentenced to life in prison last week for the death of Kejuan Mason after entering a non-negotiated guilty plea in December, the Fulton County District Attorney’s Office told the Atlanta Journal-Constitution.

Morris beat Mason to death as punishment for eating a cupcake on Oct. 21, 2017, according to the news outlet.

Morris’ sister, Glenndria Morris, stood by and watched the beating without intervening, prosecutors allege. She is reportedly facing charges of murder, aggravated assault, and cruelty to children.

Both sisters told investigators that Mason had choked on the cupcake, WXIA-TV reported.

An autopsy later determined that Mason died of blunt force trauma. He reportedly suffered bruises to his legs, back, chest, buttocks, arm, and head.

The case against Glenndria Morris is still pending.

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