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PITTSBURGH (KDKA/AP) — The man accused in the death of his fiancée’s 8-year-old son is heading to prison.

Orlando Williams, 39, was found guilty, and then received a sentence of life in prison without parole on Monday afternoon.

Williams went on trial last week on charges of homicide and child endangerment counts.

He was accused of killing the boy by slamming him onto the floor for not cleaning his room.

Authorities allege Williams had been drinking and tripped over a laundry basket in the boy’s room. They said he then angrily tried to slam the boy onto the edge of his bed but missed and the boy landed on the floor.

A defense attorney previously argued that the evidence presented wouldn’t support a charge more serious than involuntary manslaughter. She has said Williams had acted as a “father figure” to the child for years and was “inconsolable” over his death.

Attorney Dan Demarco represents the boy’s mother. She is also charged with child endangerment.

“My client is very satisfied with the verdict. This is very tragic what happened,” Demarco said. “We feel that justice definitely was served today.”

Police say two other boys in the home were also abused. Their mother faces child endangerment charges. Her trial is in mid-December.

“I represent her. I’ll be talking to the district attorney about the charges,” Demarco said. “She’s a loving, caring mother, and she’s working even to this day very hard with her children to raise her children in the proper way.”

She was not in court Monday, but her sister Lauren Anthony was.

“Very relieved and safe now. She’s been in protective custody,” she said.

Witnesses say Williams showed no emotion as he was taken to jail from the courtroom.

(© Copyright 2017 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)