A mother of two who disappeared 40 years ago was murdered by her husband, Wisconsin cold case detectives said this week.

Muskego Police charged John Bayerl, 78, of Fort Meyers, Fla., with first-degree murder in the death of 38-year-old Dona Mae Bayerl on May 6, 1979. Her body has not been found. Bayerl showed up in a Wisconsin courtroom Thursday in a wheelchair and was jailed.

The Bayerls were the parents of two girls, Jodie, 7, and Jackie, 4, at the time of the disappearance.

"The police would come I would just tell them basically what I was told from my dad I think, which was that I went to bed, he heard some noises like a door slam or something like that and when I woke up she wasn't there," daughter Jodie Jarvis said in 2017, WTMJ-TV reported Thursday. "Just imagine if you didn't know where your mother was. It's not a nice way to grow up."

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Muskego police believed Dona Mae did not leave of her own free will, according to the City of Muskego website. Police found her blood in the garage.

“A circumstantial case was developed against a suspect, but no charges were issued, because of lack evidence,” according to the site, which lists Dona Mae’s disappearance as “Cold Case #1” and also reports she was officially declared dead in 1986.

According to police, a break in the case led to Bayerl’s arrest Feb. 15 in Florida, Patch Fox Point-Bayside reported Thursday.

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The criminal complaint against Bayerl says Muskego Det. Steve Westphal went to Florida seven months ago to update Bayerl on the investigation.

After admitting cheating on his wife, Bayerl told the detective “he knows in his mind, he is not guilty of anything other than being a bad husband,” according to the complaint which WDJT-TV posted on its website Thursday.