SOUTH DAYTONA, Fla. -

Police have charged the mother of a 4-year-old boy and her boyfriend with aggravated child abuse after investigators say the pair repeatedly beat her little boy.

Investigators say Mikkia Lewis, 22, and her boyfriend, Joe McCaskell, 32, are charged with aggravated child abuse in the beating of the 4-year-old boy.

The boy was found dead on April 15 when McCaskell called to report the child wasn't breathing.

When officers arrived to the apartment in South Daytona, they found the boy lying naked on the bedroom floor, with Lewis trying to put shorts on the boy, according to the report. Paramedics said they believed the boy had been dead for hours and that the boy had been beaten all over his body.

According to the report, the boy's injuries included shoe impressions on his arms, chest, back, legs, abdomen, buttocks, a  mutilated left nipple, dislocated shoulders, hemorrhaging in the thighs and an open laceration inside of his mouth.

Lewis first said her son fell down the apartment stairs, which caused some of the injuries, deputies said. She later told investigators she twisted his left nipple and beat him with a shoe and belt because she was having behavioral issues with him, according to the report.

Local 6 spoke to Lewis' neighbor, who said he wasn't aware she had a son.

"The day before she mentioned her son was sick I said I didn't even know she had a son after two weeks," said neighbor Brian Keith. "She said he was afraid to come outside, afraid of his dad. He was afraid to go to school."

The medical examiner said in the report the abuse is believed to be chronic and occurring for much of the boy's life. According to the police report, four days before the boy's death two of his teachers did a health check on him and said he had no visible injuries on him.

Watch Local 6 News for more on this story.