Michigan man who killed 13-year-old after raping mom gets 50 to 150 years in double homicide

LANSING, Mich. — A Michigan child-killer sentenced to more than a century in prison last fall had another 50 to 125 years tacked onto his sentence last week after pleading guilty to killing a Lansing couple in a deadly home invasion.

Isaiah Gary Gardenhire, 41, was sentenced Feb. 28 in the April 28, 2021, murders of Harley Owens, 39, and his girlfriend, Kelsey Coon-Lennon, 29, in their home. Gardenhire is already imprisoned at the Bellamy Creek Correctional Facility following his November sentencing in the June 6 murder of Adrie Abigail Dembowske, 13, about 70 miles from Lansing in Mt. Pleasant.

Gardenhire, who was the boyfriend of Dembowske’s mother, went on a two-day crime spree that began when he raped the mother, who was seven months pregnant at the time. In the Mt. Pleasant case, he pleaded no contest and was sentenced to 75 to 120 years in prison.

Prison records show his earliest release date for Dembowske’s killing is in 2096, when he would be 115 years old. The dates do not appear to take into account his most recent sentence.

He fatally stabbed the teen after her mother managed to run for help. Gardenhire fled the family’s house before police arrived and ended up at the nearby Jamestown Apartments, where he holed up in a vacant unit.

While hiding at the complex, he took two tenants in an occupied unit hostage, authorities said. He repeatedly sexually assaulted the female resident.

Gardenhire then stole the couple’s Ford Fusion, which he drove to Flint Township. He turned himself in the following day as authorities conducted a large-scale manhunt.

In the April double homicide, Gardenhire was accused of going to the home Owens and Coon-Lennon shared on Baker Street in Lansing and fatally shooting the couple. According to the Lansing State Journal, their bodies were found three days later.

“There’s not really any other way to say this. Mr. Gardenhire is an unapologetic murderer,” Assistant Ingham County Prosecutor Andrew Stevens said last week. “He deserves to spend the rest of his days behind bars.”

Circuit Court Judge Joyce Draganchuk appeared to agree. As she handed down Gardenhire’s sentence, she talked about the devastation the murders have caused the victims’ families.

“This is absolutely horrific, and I have few words that could ever express how horrific this is,” Draganchuk said, according to the newspaper. “There’s no justification, no rationale. No rational human being could ever justify this.”

The motive for the double murder was not immediately clear, and Gardenhire remained silent during his sentencing hearing. The State Journal reported that Owens’ daughter wrote to the court to describe how her father’s murder left her “empty and broken.”

Owens’ obituary described him as an “artist at heart” who loved drawing, music and poetry.

“As he grew, he turned all of this into a passion for body art and always looked forward to his next tattoo,” the tribute read. “Harley loved his friends like family, listened to his music loud, ate his food spicy and washed it down with a Coke. He was a darn good cook, loved his Hondas, insisted that his hat, T-shirt and tennis shoes be spotless white and his pants baggy.

“He was a goofball at heart and never passed up a bonfire with friends or the opportunity to lend a hand or help someone smile.”

Coon-Lennon, who also left behind a young son, was described in her obituary as “a bright light, a bold, vibrant and adventurous woman that was always finding the humor in life.”

At the time of the homicides, Gardenhire was a convicted felon who had previously served time for home invasion and assault. He was not publicly named as a suspect in Owens’ and Coon-Lennon’s deaths until his arrest for the crime spree that led to Dembowske’s killing.

Gardenhire’s sentence for killing Owens and Coon-Lennon is set to run concurrently, or at the same time as his sentence in the teen’s murder.

Though he said nothing during his sentencing last week, Gardenhire expressed remorse during his November sentencing in the Dembowske case.

“I regret it. Adrie was a good child,” Gardenhire said, according to “She didn’t deserve what happened to her; neither did my other victims. I don’t expect forgiveness.”

‘Didn’t God know how much I’d miss her, Mama?’

Just nine days before Adrie’s murder, Gardenhire had been charged in Mason County with criminal sexual conduct with a child under 13. That alleged crime took place in 2015.

He was out on bond in the Mason County case when he went early June 6 to his girlfriend’s Mt. Pleasant home, where she and her four daughters were asleep. According to authorities, Michigan state troopers were dispatched around 3:15 a.m. that day to the home, located on S. Isabella Road.

There they found Adrie, the oldest of the four siblings, dying of stab wounds.

The court in November heard the chilling details of that morning from the children’s mother, whose name is being withheld because she was the victim of sexual assault. During parts of her victim impact statement, she directly addressed Gardenhire, who attended the hearing via Zoom.

The woman told the court she tried to stay as quiet as possible as she was raped so she wouldn’t wake her children. One of the girls “slept peacefully only a few feet away” from where she was assaulted.

She said Gardenhire smiled as he was “talking about cutting our unborn child out of my body while my four daughters watched,” reported.

He also threatened her daughters during the ordeal.

“Walking into the room, standing over her, showing me how you were going to slit her throat if she made one noise,” the mother told Gardenhire, according to the news site. “I knew you were going to kill me while you were doing painful and tortuous acts to me.

“I was only thinking, ‘How do I escape with my 2-, 5-, 9-, and 13-year-old,’ because I knew they were not going to be able to escape you.”

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The woman said she struggled with Gardenhire and attempted to attract the attention of neighbors, to no avail. Eventually, she was able to free herself and run next door.

“Isaiah chases me to the neighbors’, and I heard Adrie yell, ‘Mom,’ and I knew she was alive,” the mother said in court. “I continued to run to the headlights across the street to call the cops, and in those seconds, Isaiah made the devastating choice to turn back to that house.

“In those split seconds it took the cops to have my house surrounded, Isaiah made the choice to do what he did to Adrie. Only Isaiah will ever know why.”

Adrie was a fun-loving and imaginative eighth grader who hoped to someday be a lawyer, according to her obituary.

“When she made up her mind that she wanted to do something, Adrie would research it and learn how to accomplish her goal,” her family wrote. “A very smart young lady, she enjoyed investigating family history, studying about the world, learning sign language and being a part of Student Council in East Tawas.”

The teen was also known as a prankster.

“One April Fool’s Day, she and her sister flipped all the furniture upside down,” the obituary read.

Adrie’s mother told the court during Gardenhire’s sentencing that her daughter’s murder was made more painful because of his relationship with the family.

“What makes this even more horrific is that Isaiah had a bond with all of my children,” she said, according to “Making TikToks or having prank wars; every holiday, birthday, vacation, long summer days spent making memories in the sun was our favorite thing to do as a family.

“Isaiah killed all my daughters that night because they will never be the same.”

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She spoke of her daughters’ struggle to cope, recalling a comment one of the girls made after her sister’s murder.

“Didn’t God know how much I’d miss her, Mama?” the girl asked.

As the grieving mother spoke, Gardenhire paced in his cell and, at one point, retrieved food and began eating it, the news site reported.

Isabella County Circuit Judge Mark Duthie told the court the family’s ordeal was the worst he’d seen in 37 years as a prosecutor and judge.

“The only way you could characterize it, it was flat-out evil,” Duthie said. “The defendant deserves no consideration from the court. He needs to spend the rest of his life behind bars.”