An Iowa couple charged with stealing more than $163,000 from a dependent parent is also being investigated in a child's death, authorities say.

Trina Jae Mazza, 47, and Michael Damon Mazza, 49, were each charged with four counts of dependent adult abuse, first-degree theft and forgery. Trina was also charged with operating a child care center without a license, court records show.

The couple, booked Tuesday night in the Polk County Jail, were accused of taking the money from Michael's mother for months last fall.

In November, an assistant Polk County attorney asked a judge to prohibit the couple from withdrawing funds from any bank or savings associated with the dependent adult. The prosecutor also asked that the woman's financial accounts be frozen.

In those court records, an Iowa Department of Human Services adult protective worker said a financial officer advised the woman that $40,000 in suspicious checks were written on her checking account. The woman said she had not authorized the expenditures, which included a $12,000 check for a roof on the Mazza home, records show.

The woman said her daughter-in-law was paying her bills and arranging in-home services because she was "foggy." She became aware of the financial irregularities when she made a deposit and was asked about them. The bank officer asked her about her competence, noting her "forgetfulness" and "confusion," records show.

The woman hid checkbooks and other financial account information so her daughter-in-law would not find them, she told a DHS worker. The problem with doing that, she said, was that she herself forgot where she hid them, she said.

She believes her son would have known his wife wrote the checks, according to court documents. She called her daughter-in-law "a force to be reckoned with."

A child death investigation is also ongoing involving the couple, Janet Wilwerding, communications specialist for the city of Johnston, said in a written statement Wednesday.

Authorities responded to an unresponsive child at the Mazza home on Feb. 15. The child died later at a hospital, officials said.

Authorities found at the time that Trina Mazza was providing in-home child care services to seven children who were not her own. She was not registered with the state to be a child care provider, police said.

The DHS received complaints in March 2011 and September 2017 of Tina Mazza operating a child development home with more than five children at any one time, , according to court documents.

Iowa law requires in-home child care providers be registered with the state if they care for five or more children.

An investigation into the child's death suggested that Mazza continued to break that law, and she was charged with with operating a child care center without a license, a serious misdemeanor.

The cause of the child's death has not been specified. Police refused to identify the child and did not until Wednesday release any details about the death.

The Mazzas have not been charged in the child's death.

In July, Trina Mazza was charged with third-degree theft in Dallas County after officials say she used a fake check a year earlier at a Costco Wholesale in West Des Moines. The check was for more than $560, which was not honored because of insufficient funds, court records show. That case was dismissed without prejudice.

The couple did not yet have attorneys listed in court records.

No one answered when a reporter knocked on the couple's front door Wednesday morning.

Contributing: The Des Moines Register staff

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