The son of a renowned doctor played a crucial role in his father's death, as he recalls eerie sounds from decades ago.

In 1989, five days after Christmas, Collier Landry heard what sounded like "a body hitting a wall."

At 11 years old, the boy was tucked in bed, unaware that his mother, Noreen Boyle, was being brutally murdered in their Ohio home.

"The now-46-year-old told Planet Chronicle Digital that the sounds will forever remain etched in her memory, giving her sleepless nights. Despite her efforts, she couldn't prevent what may have been happening."

"As a young boy, I was asthmatic and unsure of myself. My father was large and intimidating, and I was still trying to understand my place in the world. However, when I heard my father's footsteps down the hall and saw his shoes in the doorway, I knew something significant had occurred."

Landry claimed he suddenly heard a voice "screaming inside of him." It cautioned him not to look up. He feigned sleep.

Landry stated that he believed he would not be sitting here if he had looked up.

"A Plan to Kill" on Oxygen's true-crime series explores the case of disturbed killers who meticulously planned the murder of their victims over an extended period of time.

Landry, the podcast launcher, emphasized the significance of discussing the effects of violent crimes on the offenders' children.

"Stories like these are crucial to hear, as they demonstrate that justice can be achieved, law enforcement will eventually listen, and you can obtain justice," Landry stated.

Landry described Boyle as a loving and doting mother.

"Numerous of my childhood companions cherish recollections of her," he said with delight. "She was incredibly compassionate and encouraging towards individuals. I recall each holiday season; I would have to contribute half of my toys to Toys for Tots because she wanted me to understand the significance of generosity. Additionally, she desired me to recognize how fortunate I was as a child to have a mommy and daddy, a home to reside in, and toys in my toy chest."

"Since childhood, my mother taught me the importance of sacrifice and compassion, even when it meant giving up some of the toys I liked. This lesson has stayed with me throughout my life."

Dr. John Boyle, Landry's father, was a renowned osteopath, but life at home was anything but harmonious.

Since 1983, the Boyles have resided in Mansfield, relocating from Virginia where John worked at a Navy clinic. It is said that during their marriage, John had multiple affairs.

In November 1989, Boyle filed for divorce after 22 years of marriage, accusing John of extreme mental cruelty and gross neglect. During the divorce proceedings, John bought a new home in Pennsylvania and relocated his medical practice from Mansfield to Erie.

Landry recounted his and his mother's fear of the patriarch, who was known for being a violent individual.

"My mother became downtrodden towards the end because of my father's aggression," Landry explained. "He would say horrific things like, 'I've started a new family, and I'm going to make sure you both live on the street.'"

"I believe it was when everything began to weigh heavily on my mother that she started to feel overwhelmed. Despite this, she remained optimistic and tried her best not to let it affect me. She did her utmost to remain strong for both of us."

He shared that he was optimistic that in the end, we would be okay.

In the morning, after hearing the "scary sounds," Landry rushed to his mother's room. She was absent.

He confronted his father, who claimed that "mommy took a little vacation" and there was no need to call the police.

"I knew immediately that he had hurt her," said Landry. "He told me the whole story about how she had gotten up in the middle of the night. I asked him about the thuds. He said it was my mother's purse that she had thrown at him, and it hit a wall."

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"I needed to discover what transpired," said Landry, "because he was manipulating me through gaslighting."

Landry secretly phoned Shelly Bowden, his mother's closest friend, after escaping. When police arrived at the house, Landry maintained that his mother would never abandon him. He claimed to have overheard his parents fighting, followed by a scream and a loud thud.

""Dave Messmore believed me when he arrived, and that's how we started the investigation," he said."

"I knew I was putting my life in danger, but I didn't care. I was determined to discover what happened to my mother, no matter the cost."

Authorities obtained search warrants partially based on Landry’s word.

On January 25, 1990, just a month after Boyle disappeared, the Mansfield News Journal reported that police found her body in John's new Erie home.

The outlet reported that she was wrapped in a tarp with a plastic bag covering her head and buried two feet below the basement in "soft, white clay." The basement floor was covered in a green carpet.

At 12 years old, Landry testified in his father's trial and played a crucial role in obtaining a conviction by confronting his father on the stand.

"If I did not testify against my father and he walked free, I would regret it for the rest of my life. If I had to go back and live with him because he would maintain custody as my father, he could have tortured me for the rest of my life."

"Although he haunted me in many ways, it would have been disastrous if he had been acquitted. I had to do what was right for my mother."

In January 1990, less than two weeks after Boyle disappeared, Sherri Lee Campbell gave birth to a daughter.

John remained innocent and testified for nine hours over two days in his defense. Despite this, former Richland County Prosecutor James Mayer Jr. labeled him as "probably the biggest liar I’ve ever seen."

John was found guilty of murdering Boyle and was given 20 years to life in prison for aggravated murder and 18 months for desecration of a corpse.

Landry was abandoned by both his mother's and father's families due to his resemblance to John and his refusal to recant his testimony.

"Being abandoned by your family at a young age can have a lasting impact on you, even if you were later adopted by a loving family. The feeling of loneliness and isolation can persist, making it difficult to reconcile with the love and support you received later in life."

"I do it daily," he murmured. "I step forward with one foot, smile and declare, 'Another day today.'"

Landry, who later moved to California to pursue a career as a cinematographer and director, began using his middle name as his new surname.

Landry has transformed his pain into purpose by becoming a speaker and coach, helping others navigate similar circumstances.

Landry stated that her story revolves around a true crime incident, but it also encompasses themes of healing and resilience. She emphasized that even in the face of unimaginable adversity, individuals can emerge stronger and more resilient.

"I would reassure my younger self, saying, 'You will succeed. You'll manage just fine.'"

The Associated Press contributed to this report.