A mother in Ohio has been charged with murder for allegedly plunging a collectible “short sword” that belonged to her husband into the back of her adult daughter — killing the woman last week — after grabbing it off a wall during an argument, cops say.

Terri Niner, 49, allegedly called 911 after the stabbing and spoke with a police dispatcher about fighting with her slain daughter, Ayla Mangan, 32, on July 10 and other times in the past “over some dumb stuff,” according to The Repository.

Niner”s criminal complaint and the police report, which were obtained by the local newspaper, detail the conversation she allegedly had with the police dispatcher. Her husband, Francis Niner, is facing an obstruction charge for allegedly withholding information from investigators.

Love true crime? Sign up for our newsletter, The Law&Crime Docket, to get the latest real-life crime stories delivered right to your inbox.

“Please help us, please,” Terri Niner allegedly said.

“Did you cut her?” the dispatcher asks, per the Repository.

“No, I grabbed the knife from her, and she went to throw herself backwards because she’s autistic,” Terri allegedly replied. “And when she went to throw herself backwards, it got her. And I thought it only cut her a little bit.”

The Niners were arrested by Canton police on Thursday afternoon and given a July 16 court date after being charged. Francis Niner told cops that he collects swords and displays them in his home. The one Terri allegedly used was hanging in the living room.

More from Law&Crime: ‘The back of her neck is decapitated’: Man who ‘hasn’t done anything but cause destruction’ allegedly murders girlfriend, a mother of 4, then chops up her body

Francis, who goes by “Jay,” is accused of being “untruthful” to investigators and deliberately withholding information relevant to the homicide probe in an effort “to protect” his wife, the complaint alleges. He is Mangan’s stepfather.

“The allegations are very serious,” said Elise Hamilton, senior trial counsel in the Canton Law Department, at Terri Niner’s bond hearing. She reportedly confirmed to the judge that Mangan was autistic and had the functional level of a 13-year-old.

Bond for Niner was set at $500,000.