SALT LAKE CITY (ABC4 News) – Darlene Caldwell wasn’t satisfied with the direction of a police investigation.

So the mother of Mikelle (Cannon) Caldwell took it upon herself to find justice for her murdered daughter.

The 23-year-old mother of two was killed in her north Ogden home in May 1999.

“It was horrifying news,” recalled her mother, Darlene Caldwell. “I couldn’t believe it and completely shocked.”

Mikelle’s two young children were in the home at the time of the murder. Her 3-and-a-half-year-old witnessed the shooting.

“He knew what had happened and he kept saying the bad man pointed the gun at his mom and shot her,” Caldwell said.

Thomas Rebillot claimed it was an accident and eventually charged with negligent homicide, a Class A misdemeanor.

But then charges were dismissed by the Weber County attorney.

“I kept asking them ‘why?'” the mother said. “What was going on? What were they doing?”

She was told about double jeopardy. If Rebillot pleaded guilty to the misdemeanor they would never be able to prosecute him for a future charge of murder. Detectives with the Weber County Sheriff’s office wanted to continue their investigation.

But Caldwell didn’t have faith in them and began investigating herself.

For the next year, she went into the drug underworld to learn more of Rebillot. Caldwell said she visited known drug houses and met with shady and dangerous characters.

“I went to (possible witness) home and he greeted me with a gun,” she said.

Caldwell left but claimed he shot and missed her. She filed a complaint with police but didn’t recall the man ever being charged with any crime.

But eventually it paid off. She was given permission to interview Brian Rebillot who was in prison at the time. He was Thomas Rebillot’s brother.

Brian told her (Thomas) boasted “it was the perfect murder and he got away with it.”

A detective was present when Brian Rebillot offered the statement to Caldwell. It became part of the record as both Caldwell and the detective conducted joint investigations.

Nearly a year later, she turned over her findings to the detective. They combined the case and presented it to the Weber County Attorney’s Office for possible charges.

Rebillot was charged with capital murder but he pleaded guilty to avoid a death sentence. He has been in prison since 2001.

In December, Rebillot appeared before the Utah Board of Pardons. He is now eligigle for parole. For the first time, he issued Mikelle’s family an apology.

“There’s no words that can ever describe how I feel or change anything that I did,” he told the hearing officer. “But I am sorry.”

He told the hearing officer he is no longer the same person who murdered Mikelle.

But Darlene Caldwell brushed aside the attempt at an apology. She said Rebillot is known to make statements that are to his benefit.

Mikelle Caldwell’s son who is now 24 years old also testified at the hearing and reminded Rebillot that he watched him pull the trigger. Gavyn Caldwell read from a prepared statement.

“A young toddler infatuated and in love with his beautiful mother at only 3 years old safely walks down the hall and begins to descend the stairs,” said Caldwell as he held back tears. “Thirsty, he wants to ask his mother for a glass of water. The young toddler never makes it to the bottom of the stairs as he watches a man enter into his home and pulls the trigger ending mom’s life. In confusion and shock and terror the young toddler runs upstairs and hides under the bed not completely understanding what had happened.”

Darlene Caldwell said Gavyn has gone through years of therapy to overcome the horror that he witnessed. She said he has managed to move on but remained haunted by what happened.

Gavyn and her sister were eventually adopted and raised by their grandparents. Both are now married.

As for Mikelle Caldwell, justice finally came her way, but her mother took no satisfaction for her role in making it happen.

“I was glad he was off the streets,” she said. “I was glad that he couldn’t hurt anyone else.”

Darlene Caldwell said she is also grateful to the one detective who kept investigating the case and was willing to accept her findings as well. She called him her “hero.”

As for Rebillot, his parole was denied and will have to serve another 10 years.