A man will plead guilty to murder for the death of his 3-year-old foster son left bound up in a closet while he went to a family reunion, his attorney and the Clermont County prosecutor said Monday.

David Carroll Jr. agreed to accept a plea deal with a sentence of 15 years to life in prison, plus an additional one year for gross abuse of a corpse, said defense attorney Cathy Adams and Don White, Clermont County prosecutor. White said the agreement was subject to written confirmation and a judge's approval at a plea hearing Tuesday.

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A jury last week convicted Carroll's wife, Liz, 30, of murder and six other charges, including involuntary manslaughter and kidnapping, in the death of Marcus Fiesel. She was sentenced to a total of 54 years to life in prison.

Prosecutors agreed to drop six charges against David Carroll. Carroll, 29, faced the same seven charges as his wife, plus the eighth charge of gross abuse of a corpse, in a trial scheduled for March 19 in Batavia. Prosecutors say he burned the boy's body and dumped the remains in the Ohio River.

The Carrolls were charged with causing the Fiesel's death by leaving the developmentally disabled boy bound cocoon-like in a closet for two days while they went to a weekend family reunion in Kentucky in August.

Prosecutors say the Carrolls found Fiesel dead when they returned to their home just east of Cincinnati. The Carrolls told authorities the child had wandered off or had been snatched from a park in suburban Cincinnati, sparking a search by thousands of volunteers.

White said prosecutors were willing to offer the deal to avoid a trial and because they're confident Carroll won't ever be paroled.

"I firmly believe that a guy like this, with this set of facts and circumstances, will be in prison the rest of his life," White said. "I think he should serve life and he will."

Adams said after discussing a plea over the weekend and again Monday morning, Carroll decided to take the deal. She said a key factor was the possibility that prosecutors would call as a witness the Carrolls' oldest, who is about 7, of four children.

A prosecutor said last week the boy has said Fiesel's hands were bound repeatedly by David Carroll.

"He did not want to put his son through that," Adams said.

Liz Carroll's conviction and sentence also played a role in the decision.

"It certainly had an impact," she said. "It also had more of an impact because he has now lost his wife."

Prosecutors in Hamilton County, where the parents claimed the boy had disappeared, also agreed to drop lesser charges against David Carroll of perjury and inducing panic, Adams and White said.