CHICAGO (CBS) — A Riverdale man has been charged with killing his elderly mother-in-law on Sunday in south suburban Chicago Heights.

Investigators discovered 82-year-old Australia Landingham’s body inside her home in the 2300 block of South Halsted Street in Chicago Heights around 5:15 p.m. Sunday.

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Police initially responded to a report she fell down some stairs, but n autopsy determined she died of multiple blunt force injuries, and her death was ruled a homicide, according to the Cook County Medical Examiner’s office.

Australia Landingham, 82, was found beaten to death inside her home in Chicago Heights on May 27, 2018. (Photo supplied to CBS)

Her nephew said she was about to celebrate her 50th wedding anniversary on Friday.

“She loved everyone,” Isaiah Allen said. “She was a God-fearing woman and she would give you anything.”

Friday morning, Chicago Heights police announced Landingham’s son-in-law, 48-year-old Charles Williams, of Riverdale, had been charged with first-degree murder.

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Charles Williams is charged with first-degree murder in the death of his mother-in-law, Australia Landingham. (Credit: Chicago Heights Police)

Investigators did not say how they tied Williams to the crime.

Several people who know Landingham said she was taking financial care of Williams on a regular basis.

At least two neighbors said they saw Williams casually talking to police at the crime scene.

Landingham’s adopted son, Ezekiel Landingham, said he had an uneasy feeling about Williams for years.

“I just didn’t want him to get away,” he said. “You hear about so many stories like this, or other stories that are similar that just go unsolved.”

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Williams was due to appear for a bond hearing Friday afternoon at the Markham Courthouse.